Do you expect them to have a 'crab trainer' to train it to 'walk' around? yeah, right, I mean Hollywood spends million of dollars on stupid stuff, but I don't think they would do anything like that. also, i think this movie was sort of low-budget, cuz you can tell from the color quality and stuff, plus the fact that they are in REAL places, since most movies have sets, you know? costs less for the real thing I would imagine...
Okay, I've seen the movie, and, I don't know about the one scene where the crab crawls, but in all the other scenes it's pretty obvious that the crab is fake. The movie IS pretty low budget, but you've got to look past the cheesiness and just enjoy the cute little love film!