I tend to agree with you, as well. I'm finding that a lot of the artists whose music I enjoy (mostly alternative country/folk) fall into the "enemy camp" so to speak. I will continue to listen to them and purchase new releases if I feel so inclined.
What I won't do is seek out any products from artists I haven't heard before who are "celiberals." For example, I was once curious to hear what Steve Earle was all about...this was before John Walker Blues. I still have never heard his music, and now I don't plan to ever buy anything from him.
It's a real shame that Steve Earle has turned out to be so anti-American. I really like his musical style and he has some great songs (aside from that Johnny Walker song). My favorite Steve Earle song is Copperhead Road. But no, I won't be buying any more of his CD's - darn it!