The simple fact is they WERE accepted as credible in all but one of the offices. It was a successful sting.

In Bowling for Columbine, Moore made a number of statements about the NRA that were factually untrue, and the NRA was never given a chance to respond. In "Roger and Me" he makes it look as though the president of GM wouldn't speak to him, when in fact he received a one-on-one interview (BEFORE he bought his one share of stock) -- again, there's no place for a response to the accusation in the movie. I could go on.

YOU think they didn't fit the part they were playing -- and you're welcome to think that. The "tax preparers" at ACORN had no trouble believing them.