To tell you the truth I don't mind the "I believe" chant. It is unique to the American culture and you don't hear it at other soccer matches around the world. So I like that.
What can I say. I like unique cheers. (I know it is not unique for other sports, but it is for futbol.)
It doesn't bother me. The entire stadium wants to do a chant. Great! I would never start one though. And I think we have some much worse ones.