Other mistake: Jackie comes out of her room while Fez has Caroline over, stating that she has to use the bathroom. However, in a previous episode, during Fez and Kelso's fight for the same room, it is the room that "has its own bathroom." (00:16:00)
Other mistake: When Bob comes to order from the clown, he gets told to go away since they're closed. He starts pulling away, but you can see he doesn't leave the frame quickly. The edge of the car is still visible when the gang is sneaking back over.
Answer: It's Ashton Kutcher's dog.