diff --git a/registrasion/controllers/cart.py b/registrasion/controllers/cart.py
index 2ff9f171..283c3119 100644
--- a/registrasion/controllers/cart.py
+++ b/registrasion/controllers/cart.py
@@ -240,12 +240,11 @@ class CartController(object):
             by_cat[product.category].append((product, quantity))
 
         # Pre-annotate categories
-        r = CategoryController.attach_user_remainders(self.cart.user, by_cat)
-        with_remainders = dict((cat, cat) for cat in r)
+        remainders = CategoryController.user_remainders(self.cart.user)
 
         # Test each category limit here
         for category in by_cat:
-            limit = with_remainders[category].remainder
+            limit = remainders[category.id]
 
             # Get the amount so far in the cart
             to_add = sum(i[1] for i in by_cat[category])
diff --git a/registrasion/controllers/category.py b/registrasion/controllers/category.py
index 9db8ca9e..4681f48b 100644
--- a/registrasion/controllers/category.py
+++ b/registrasion/controllers/category.py
@@ -39,17 +39,16 @@ class CategoryController(object):
         return set(i.category for i in available)
 
     @classmethod
-    def attach_user_remainders(cls, user, categories):
+    def user_remainders(cls, user):
         '''
 
         Return:
-            queryset(inventory.Product): A queryset containing items from
-            ``categories``, with an extra attribute -- remainder = the amount
-            of items from this category that is remaining.
+            Mapping[int->int]: A dictionary that maps the category ID to the
+            user's remainder for that category.
+
         '''
 
-        ids = [category.id for category in categories]
-        categories = inventory.Category.objects.filter(id__in=ids)
+        categories = inventory.Category.objects.all()
 
         cart_filter = (
             Q(product__productitem__cart__user=user) &
@@ -73,12 +72,4 @@ class CategoryController(object):
 
         categories = categories.annotate(remainder=remainder)
 
-        return categories
-
-    def user_quantity_remaining(self, user):
-        ''' Returns the quantity of this product that the user add in the
-        current cart. '''
-
-        with_remainders = self.attach_user_remainders(user, [self.category])
-
-        return with_remainders[0].remainder
+        return dict((cat.id, cat.remainder) for cat in categories)
diff --git a/registrasion/controllers/product.py b/registrasion/controllers/product.py
index 0e2e984f..0810902b 100644
--- a/registrasion/controllers/product.py
+++ b/registrasion/controllers/product.py
@@ -34,16 +34,13 @@ class ProductController(object):
         if products is not None:
             all_products = set(itertools.chain(all_products, products))
 
-        categories = set(product.category for product in all_products)
-        r = CategoryController.attach_user_remainders(user, categories)
-        cat_quants = dict((c, c) for c in r)
-
+        category_remainders = CategoryController.user_remainders(user)
         product_remainders = ProductController.user_remainders(user)
 
         passed_limits = set(
             product
             for product in all_products
-            if cat_quants[product.category].remainder > 0
+            if category_remainders[product.category.id] > 0
             if product_remainders[product.id] > 0
         )