The better question is who I would go to, b/c I view concerts as more of an inconvenience than anything. I can listen to the music at any time I want now and I'm not an experience kind of person so it's just not appealing.

But in the spirit of your question there are WAY too many to name them but I'll name my least favorite band I can ever imagine:

Cigarettes After Sex

Good god it's the whiniest horrific shit I've ever heard in my life. I'd burn the tickets so that no one else has to experience that nonsense.