There's a door dividing the kitchen and living room. Most of the time, there isn't.
When Apu opens the fake non-alcoholic beer fridge, the stairs are frozen. It is a fake fridge, the stairs lead to the roof.
In the short film with Troy McClure about the slaughterhouse, the perspective of the building is impossible, as both ends appear to face the camera.
Despite being vegetarian, Apu is seen when Homer organizes a barbecue.
The wolf is demanding all three pigs to come out of a straw house. However, in the storybook, the straw house is the first house attacked by the wolf, and should only have one pig. Alternately, the pigs should be in the brick house.