Thats a fair call and I agree, though have you ever heard a band for the first time live, and thought it was so bad that you were put off checking out an album? I'd say bias's do occur like that, and vice versa for hearing a really poor studio album thus not wanting to pay a few bucks to go see them at your local, no matter how good the show might be.
If the first impression is that strong sometimes you probably would pass over what could be a really good thing.