I hate it when I've been really into a band/musician for a while and most people aren't aware of them and then all of a sudden they become super popular and i'm almost embarrassed to admit my interest in them. It nearly killed me when Lily Allen and Amy Winehouse debuted in America. I'm such and Anglophile and I get so territorial, so when artists I'd been geeking out over became huge here, i was quite annoyed.
(i also hate it when i get territorial over music. it's so juvenile but i can't help it!)