Really, tj? Apple? UGH.
But for reals, it seems you just found a bad group of genuinely rude people. I mean, from the way you say it, that girl who said "ugh" wasn't saying it jokingly like a "lolmac" thing that we do here. And I think its a common trend with the wild Zappa fan to look down at other "prog/progressive" bands because they put Zappa on such a high pedestal (I am of course basing this on a total of three hardcore Zappa fans that I have met and nothing else. That was a joke.
) but that was still a pretty rude thing to say as well. A much more tactful (and fun!) way to go about it would be to say "Ah, DT? Yeah, not my favorite thing. Hey, have you heard *insert band here*?"
And people switching songs that you pick, especially when they're as people-friendly as "Limelight," is one of my biggest pet peeves. I don't switch the channel when Ke$ha's playing, someone should have the respect not to change the channel when Rush is playing unless they ask very politely if we could listen to something else.