Turtle film designs?

[thundermaster612]

This is a thread about TMNT designs right? I guess what I'm about to ask kind of counts but I just watched the full B-Roll for the movie and I saw what Bebop and Rocksteady look like with mo-cap suits. My question is, how come the turtles need mo-cap shells but Bebop doesn't need a mo-cap stomach or something, in fact they should have more stuff on because they are bigger than the turtles but in real life they're actually smaller than the turtle actors... whats up with that? How come the turtles need extra stuff for the shell but B&R don't need extra stuff for... everything...