That's really bad! I can't believe that people let their dogs do something like that. If I see my dog starting to be bullyish, which is very rare, I go over and make sure she knows that it is wrong and I won't put up with it. In my opinion, they've got to be raised to know what's acceptable and what's not. Obviously, these people either don't know the difference themselves, or they didn't teach it to their dogs and don't really care if their dogs know it or not!