Always got to love artists who moan about people listening to their music for free. To an extent Youtube gives artists free advertising. They are some artists I listen to now that I would never have heard of without sites such as Youtube. The band "Sunset Sons" springs to mind. I first heard one of their tracks on a Youtube advert. Since then I've bought most of their EP's and their debut album.
I'm willing to bet artists have gained a lot of customers over the years through Youtube and other sites.
Matthew, if an artist or group puts their music on Youtube then I would agree with you but we both know that is not the case. I can go on Youtube and at times get entire albums/cds worth of music that someone other than the artist/group put on Youtube. While just opinion, I find your logic flawed.