Continuity mistake: At the Randall Curtis's Ranch we see Randall Curtis ride off on a Ton-Ton to go to the video store but in a scene only a few minutes later we see Marge and Homer drunk, tossing him around. Unless the video store is on the ranch or very close by this doesn't seem possible for someone so determined to rent movies.
Continuity mistake: When the family are watching Krusty Komedy Klassics, at the beginning of the show, they all have grey tables, with their dinner. But when Bart asks for milk, Marge gets up to get it and her table has disappeared. When she comes back the table has re-appeared.
Continuity mistake: When the Ranger stops the Simpsons' car at the start of the episode, watch his "class ring". When he puts his hands inside the car it's on the left hand. However, the flies later eat his hand and take his ring, and it's suddenly his right hand they ate and took it from.
Continuity mistake: When Bart gets on the bus, we see one of the twins sitting near The Front of the bus. In the next shot, we see both twins sitting at the back. The shot after that, we see the twin near The Front again, running to the back. (00:10:30)
Continuity mistake: When the store is being robbed, Homer throws his bag to the side and it lands face down near the stand of chips Homer jumps into. But when they are watching the video of this incident later, the bag is standing upright, far away from the spot it previously was at.