I'm used to comments like that. It still shocks me when people say 'Who is From First to Last?' or 'Who is Reggie And the Full Effect?', but it's not as surprising since a lot of music I listen to is more not-mainstreamish. I would be stunned if someone hadn't heard of Depeche Mode (who I haven't really listened to, honestly, so I don't know if I like them or not), or NiN. Seriously, who hasn't heard of those two bands?!