I was just thinking about Monsters Inc.: Mike and Sulley to the Rescue and it occured to me that in the queue (a transit hub) and at the very beginning of the ride, they make a point of telling you that you're in a taxi, going on a tour of Monstropolis, when the breach of "child security" happens. They give you a more specific role to play than some of the older dark rides do (where you're basically just going through the environments and following the characters). However, after that point, the idea that you're in a taxi is never brought up again. Suddenly, we're just following Mike and Sulley. The "taxi" drives through a restaurant, a factory and even a bathroom and none of the characters seem to notice. The taxis on Roger Rabbit and the cars on Mr. Toad also drive through indoors environments, but they're supposed to be careening out of control, whereas the Monster's Inc. taxi seems to be driving slowly and calmly.
(Note that on ToT, even though its a very strange service elevator with chairs and seatbelts in it, the idea that you're in an elevator is never forgotten )