Actually, what I meant by the "once" comment is that rather than buy the cd, I might be happy hearing it live the one time.
There are many groups I go see (not particularly jazz) that I have no intention of buying music from, but I'm willing to go see them perform. My music collection is getting out of hand, so sometimes it's better to just enjoy the music in the now and let it go. Of course, sometimes seeing someone live does make me buy their music too.