diff --git a/src/pretix/base/models/items.py b/src/pretix/base/models/items.py
index 6d4a5291ad..7aa035970a 100644
--- a/src/pretix/base/models/items.py
+++ b/src/pretix/base/models/items.py
@@ -913,8 +913,6 @@ class Item(LoggedModel):
         :raises ValueError: if you call this on an item which has variations associated with it.
                             Please use the method on the ItemVariation object you are interested in.
         """
-        if not trust_parameters and not subevent and self.event.has_subevents:
-            raise TypeError('You need to supply a subevent.')
         check_quotas = self._get_quotas(ignored_quotas=ignored_quotas, subevent=subevent)
         quotacounter = Counter()
         res = Quota.AVAILABILITY_OK, None
diff --git a/src/pretix/base/services/cart.py b/src/pretix/base/services/cart.py
index 9e1c2e45fc..a59735daf2 100644
--- a/src/pretix/base/services/cart.py
+++ b/src/pretix/base/services/cart.py
@@ -793,9 +793,7 @@ class CartManager:
         operations = []
 
         for i in items:
-            if self.event.has_subevents:
-                if not i.get('subevent') or int(i.get('subevent')) not in self._subevents_cache:
-                    raise CartError(error_messages['subevent_required'])
+            if self.event.has_subevents and i.get('subevents'):
                 subevent = self._subevents_cache[int(i.get('subevent'))]
             else:
                 subevent = None
diff --git a/src/pretix/base/services/cross_selling.py b/src/pretix/base/services/cross_selling.py
index 3166747158..ea3cada949 100644
--- a/src/pretix/base/services/cross_selling.py
+++ b/src/pretix/base/services/cross_selling.py
@@ -58,9 +58,9 @@ class CrossSellingService:
             result = (
                 (DummyCategory(category, subevent),
                  self._prepare_items(subevent, items_qs, discount_info),
-                 f'subevent_{subevent.pk}_')
+                 f'subevent_{subevent.pk}_' if subevent else '')
                 for subevent in subevents
-                for (category, items_qs, discount_info) in self._applicable_categories(subevent.pk)
+                for (category, items_qs, discount_info) in self._applicable_categories(subevent.pk if subevent else 0)
             )
         else:
             result = (
diff --git a/src/pretix/control/forms/item.py b/src/pretix/control/forms/item.py
index b90592ffbd..b0a37b14e9 100644
--- a/src/pretix/control/forms/item.py
+++ b/src/pretix/control/forms/item.py
@@ -342,7 +342,6 @@ class QuotaForm(I18nModelForm):
                 }
             )
             self.fields['subevent'].widget.choices = self.fields['subevent'].choices
-            self.fields['subevent'].required = True
         else:
             del self.fields['subevent']
 
diff --git a/src/pretix/presale/templates/pretixpresale/event/index.html b/src/pretix/presale/templates/pretixpresale/event/index.html
index 633f3c90bb..de43c5ddfa 100644
--- a/src/pretix/presale/templates/pretixpresale/event/index.html
+++ b/src/pretix/presale/templates/pretixpresale/event/index.html
@@ -185,69 +185,68 @@
             </div>
             {% eventsignal event "pretix.presale.signals.front_page_top" request=request subevent=subevent %}
         {% endif %}
-
-        {% if ev.presale_is_running or event.settings.show_items_outside_presale_period %}
-            <form method="post" data-asynctask
-                    data-asynctask-headline="{% trans "We're now trying to reserve this for you!" %}"
-                    data-asynctask-text="{% blocktrans with time=event.settings.reservation_time %}Once the items are in your cart, you will have {{ time }} minutes to complete your purchase.{% endblocktrans %}"
-                    action="{% eventurl request.event "presale:event.cart.add" cart_namespace=cart_namespace %}?next={{ cart_redirect|urlencode }}&next_error={{ request.path|urlencode }}">
-                {% csrf_token %}
-                <input type="hidden" name="subevent" value="{{ subevent.id|default_if_none:"" }}" />
-                {% if ev.seating_plan_id and event.settings.seating_choice %}
-                    {% if event.has_subevents %}
-                        {% eventsignal event "pretix.presale.signals.render_seating_plan" request=request subevent=subevent %}
-                    {% else %}
-                        {% eventsignal event "pretix.presale.signals.render_seating_plan" request=request %}
-                    {% endif %}
+    {% endif %}
+    {% if ev.presale_is_running or event.settings.show_items_outside_presale_period %}
+        <form method="post" data-asynctask
+                data-asynctask-headline="{% trans "We're now trying to reserve this for you!" %}"
+                data-asynctask-text="{% blocktrans with time=event.settings.reservation_time %}Once the items are in your cart, you will have {{ time }} minutes to complete your purchase.{% endblocktrans %}"
+                action="{% eventurl request.event "presale:event.cart.add" cart_namespace=cart_namespace %}?next={{ cart_redirect|urlencode }}&next_error={{ request.path|urlencode }}">
+            {% csrf_token %}
+            <input type="hidden" name="subevent" value="{{ subevent.id|default_if_none:"" }}" />
+            {% if ev.seating_plan_id and event.settings.seating_choice %}
+                {% if event.has_subevents %}
+                    {% eventsignal event "pretix.presale.signals.render_seating_plan" request=request subevent=subevent %}
+                {% else %}
+                    {% eventsignal event "pretix.presale.signals.render_seating_plan" request=request %}
                 {% endif %}
+            {% endif %}
 
-                {% if waitinglist_seated %}
-                    <aside class="front-page" aria-labelledby="waiting-list">
-                        <h3 id="waiting-list" class="sr-only">{% trans "Waiting list" %}</h3>
-                        <div class="row">
-                            <div class="col-md-8 col-sm-6 col-xs-12">
-                                <p>
-                                    {% blocktrans trimmed %}
-                                        Some of the categories in the seating plan above are currently sold out. If you want, you can add yourself to the
-                                        waiting list. We will then notify if seats are available again.
-                                    {% endblocktrans %}
-                                </p>
-                            </div>
-                            <div class="col-md-4 col-sm-6 col-xs-12">
-                                <a href="{% eventurl event "presale:event.waitinglist" cart_namespace=cart_namespace|default_if_none:"" %}{% if subevent %}?subevent={{ subevent.pk }}{% endif %}" class="btn btn-default btn-block">
-                                    <span class="fa fa-plus-circle" aria-hidden="true"></span>
-                                    {% trans "Join waiting list" %}
-                                </a>
-                            </div>
-                            <div class="clearfix"></div>
+            {% if waitinglist_seated %}
+                <aside class="front-page" aria-labelledby="waiting-list">
+                    <h3 id="waiting-list" class="sr-only">{% trans "Waiting list" %}</h3>
+                    <div class="row">
+                        <div class="col-md-8 col-sm-6 col-xs-12">
+                            <p>
+                                {% blocktrans trimmed %}
+                                    Some of the categories in the seating plan above are currently sold out. If you want, you can add yourself to the
+                                    waiting list. We will then notify if seats are available again.
+                                {% endblocktrans %}
+                            </p>
                         </div>
-                    </aside>
-                {% endif %}
-
-                <h2 class="sr-only">{% trans "Products" %}</h2>
-                {% include "pretixpresale/event/fragment_product_list.html" %}
-                {% if ev.presale_is_running and display_add_to_cart %}
-                    <div class="front-page">
-                        <div class="row">
-                            <div class="col-md-4 col-md-offset-8 col-xs-12">
-                                <button class="btn btn-block btn-primary btn-lg" type="submit" id="btn-add-to-cart">
-                                    {% if request.event.settings.redirect_to_checkout_directly %}
-                                        {% if allfree %}
-                                            <i class="fa fa-check" aria-hidden="true"></i> {% trans "Register" context "free_tickets" %}
-                                        {% else %}
-                                           <i class="fa fa-shopping-cart" aria-hidden="true"></i> {% trans "Proceed with checkout" %}
-                                        {% endif %}
-                                    {% else %}
-                                        <i class="fa fa-shopping-cart" aria-hidden="true"></i> {% trans "Add to cart" %}
-                                    {% endif %}
-                                </button>
-                            </div>
-                            <div class="clearfix"></div>
+                        <div class="col-md-4 col-sm-6 col-xs-12">
+                            <a href="{% eventurl event "presale:event.waitinglist" cart_namespace=cart_namespace|default_if_none:"" %}{% if subevent %}?subevent={{ subevent.pk }}{% endif %}" class="btn btn-default btn-block">
+                                <span class="fa fa-plus-circle" aria-hidden="true"></span>
+                                {% trans "Join waiting list" %}
+                            </a>
                         </div>
+                        <div class="clearfix"></div>
                     </div>
-                {% endif %}
-            </form>
-        {% endif %}
+                </aside>
+            {% endif %}
+
+            <h2 class="sr-only">{% trans "Products" %}</h2>
+            {% include "pretixpresale/event/fragment_product_list.html" %}
+            {% if ev.presale_is_running and display_add_to_cart %}
+                <div class="front-page">
+                    <div class="row">
+                        <div class="col-md-4 col-md-offset-8 col-xs-12">
+                            <button class="btn btn-block btn-primary btn-lg" type="submit" id="btn-add-to-cart">
+                                {% if request.event.settings.redirect_to_checkout_directly %}
+                                    {% if allfree %}
+                                        <i class="fa fa-check" aria-hidden="true"></i> {% trans "Register" context "free_tickets" %}
+                                    {% else %}
+                                       <i class="fa fa-shopping-cart" aria-hidden="true"></i> {% trans "Proceed with checkout" %}
+                                    {% endif %}
+                                {% else %}
+                                    <i class="fa fa-shopping-cart" aria-hidden="true"></i> {% trans "Add to cart" %}
+                                {% endif %}
+                            </button>
+                        </div>
+                        <div class="clearfix"></div>
+                    </div>
+                </div>
+            {% endif %}
+        </form>
     {% endif %}
     {% if show_vouchers %}
         <aside class="front-page" aria-labelledby="redeem-a-voucher">
diff --git a/src/pretix/presale/views/event.py b/src/pretix/presale/views/event.py
index fe54f21eb8..35f12f28d7 100644
--- a/src/pretix/presale/views/event.py
+++ b/src/pretix/presale/views/event.py
@@ -194,55 +194,54 @@ class EventIndex(EventViewMixin, EventListMixin, CartMixin, TemplateView):
 
         context['allow_waitinglist'] = context['ev'].waiting_list_active and context['ev'].presale_is_running
 
-        if not self.request.event.has_subevents or self.subevent:
-            # Fetch all items
-            items, display_add_to_cart = prepare_item_list_for_shop(
-                self.request.event,
-                subevent=self.subevent,
-                filter_items=self.request.GET.getlist('item'),
-                filter_categories=self.request.GET.getlist('category'),
-                require_seat=None,
-                channel=self.request.sales_channel,
-                memberships=(
-                    self.request.customer.usable_memberships(
-                        for_event=self.subevent or self.request.event,
-                        testmode=self.request.event.testmode
-                    ) if getattr(self.request, 'customer', None) else None
-                ),
-            )
+        # Fetch all items
+        items, display_add_to_cart = prepare_item_list_for_shop(
+            self.request.event,
+            subevent=self.subevent,
+            filter_items=self.request.GET.getlist('item'),
+            filter_categories=self.request.GET.getlist('category'),
+            require_seat=None,
+            channel=self.request.sales_channel,
+            memberships=(
+                self.request.customer.usable_memberships(
+                    for_event=self.subevent or self.request.event,
+                    testmode=self.request.event.testmode
+                ) if getattr(self.request, 'customer', None) else None
+            ),
+        )
 
-            context['waitinglist_seated'] = False
-            if context['allow_waitinglist']:
-                for i in items:
-                    if not i.allow_waitinglist or not i.requires_seat:
-                        continue
+        context['waitinglist_seated'] = False
+        if context['allow_waitinglist']:
+            for i in items:
+                if not i.allow_waitinglist or not i.requires_seat:
+                    continue
 
-                    if i.has_variations:
-                        for v in i.available_variations:
-                            if v.cached_availability[0] != Quota.AVAILABILITY_OK:
-                                context['waitinglist_seated'] = True
-                                break
-                    else:
-                        if i.cached_availability[0] != Quota.AVAILABILITY_OK:
+                if i.has_variations:
+                    for v in i.available_variations:
+                        if v.cached_availability[0] != Quota.AVAILABILITY_OK:
                             context['waitinglist_seated'] = True
                             break
+                else:
+                    if i.cached_availability[0] != Quota.AVAILABILITY_OK:
+                        context['waitinglist_seated'] = True
+                        break
 
-            items = [i for i in items if not i.requires_seat]
-            context['itemnum'] = len(items)
-            context['allfree'] = all(
-                item.display_price.gross == Decimal('0.00') and not item.mandatory_priced_addons
-                for item in items if not item.has_variations
-            ) and all(
-                all(
-                    var.display_price.gross == Decimal('0.00')
-                    for var in item.available_variations
-                ) and not item.mandatory_priced_addons
-                for item in items if item.has_variations
-            )
+        items = [i for i in items if not i.requires_seat]
+        context['itemnum'] = len(items)
+        context['allfree'] = all(
+            item.display_price.gross == Decimal('0.00') and not item.mandatory_priced_addons
+            for item in items if not item.has_variations
+        ) and all(
+            all(
+                var.display_price.gross == Decimal('0.00')
+                for var in item.available_variations
+            ) and not item.mandatory_priced_addons
+            for item in items if item.has_variations
+        )
 
-            # Regroup those by category
-            context['items_by_category'] = item_group_by_category(items)
-            context['display_add_to_cart'] = display_add_to_cart
+        # Regroup those by category
+        context['items_by_category'] = item_group_by_category(items)
+        context['display_add_to_cart'] = display_add_to_cart
 
         context['cart'] = self.get_cart()
         context['has_addon_choices'] = any(cp.has_addon_choices for cp in get_cart(self.request))