Maybe it would be different if you did the tags yourself. I think most taggers wouldn't mind seeing their tags in other people's works as it would be to their success that they even tagged your image. To capitolize off it is another thing. I'd be a little mad to know that someone like yourself made money off my tag and wasn't letting me in on the cut....as "it is my tag" so to speak. They did the work and you take a picture of it to make money....you're dealing with gangsters wanting money just like you. I think it should be free. I live in L.A. I can get pictures of tags, bombs, and peaces anywhere I want for free. Try tagging walls yourself then you can make the money. Until then...I guess don't get caught slippin' in enemy territory.