I have to confess I do this all the time, and I might have missed out on a lot of good music due to avoiding a band because I dislike their name. The thing is though, every single time I've gone 'What a stupid name' and then accidentally come across a song or two by said band later, I've found the music to be awful too. Recent examples: Imagine Dragons, Alt J, Tame Impala. As of now, I think this prejudice has worked as a pretty efficient filter for me, there's just too much music out there to listen to it all. Do other people do this too?
Of course I realise this is a very subjective thing, and maybe I'm just stuck up. I'd love to be proven wrong, so feel free to post music you like by bands you think have terrible names. Or you know, terrible music by bands with terrible names, whatever you feel like.