I used to be like you, SimontheMime. Then I grew up and actually opened my mind to other genres of music.
Seriously, all I listened to were Tool, Opeth, Dream Theater and other such metal and prog bands. I heaped scorn upon those who listened to rap and hip hop, listened to "manufactured" pop bands etc etc (or even worse, bands like Limp Bizkit to which pre-pubescent kids listened and considered themselves hard because the "f" word was used indiscriminately).
Then one song changed it all: 'Get By' by Talib Kweli. This one song had it all, soaring vocals, an awesome hook, nice flow and socially aware lyrics. I listened, and listened, and listened to this song.
But I thought all hip hop was crap about bling bling and shootin' fools who was runnin' on my block!
Wrong. So this opened my eyes to the world of hip hop, and I thought well, if hip hop is this good, maybe everything I listen doesn't have to be underground, or true Norwegian black metal, or so full of pseudo-psychological self-analysis and obscure Lithuanian poetry references I can hardly concentrate on the goddamn song without running to the State Library to check up on Lachrymology or other such crap (seriously, I love Tool, always have and always will, but I get tired of the overanalysis of the vast majority of their tracks).
I listen to Eminem because I think he's a brilliant satirist. I listen to Britney Spears because 'Toxic' is like the catchiest song I've heard in my life. I listen to Nas because I love his flows and his message. I listen to Arch Enemy because sometimes you need to cut sick. I listen to Tool, Muse and Opeth because sometimes I too want to feel intellectually superior and feed my ego.
And I listened to The Beatles, Pink Floyd and Led Zeppelin because they're seminal, or so the vast majority of people told me. That's fine and all, but I'm not really digging it.
Respect my musical choices and I'll respect yours. I'm sure that your musical tastes will evolve, as mine did, and you'll someday see where I'm coming from.