I think it's kinda funny (ironic?) how some people I know really *cringe* or yell "sellout" when they hear a great song being used on a TV or radio commercial. It's almost as if they'd rather hear crappy music on them instead. I have no problem with it, for the most part because it means the artist is actually getting PAID for once (hurray for them!) and it means I get to hear a great tune on a commercial once in a while instead of some hip hop or Phil Collins bullshit. It also means that their music is being heard by a HUGE audience... and primarily an audience of TV zombies whose only other exposure to music of ANY kind is the crap they hear on commercial radio, in movies, or somehow convince themselves is good like the crap you hear on stupid shows like American Idol. But whether or not you like it or not is beside the point entirely, because it's up to the individual artist to determine what happens with their music. If they want to sell the rights to a marketing agency so it's used to sell shampoo or cars, then that's their right, and you HAVE to respect their right to do what they want with their music. Because it belongs to THEM, not to you. Just because you "heard it first" or love it so much that it changes your life doesn't mean you own it. Plus, you never really know how you would respond to an offer like that if the shoe was on the other foot.
End of rant. ;)