I don't know, John.  The watchdogs that be sometimes drop the ball where some fo these products are concerned.  It might be out of pure ignorance that questionable content do make it to the marketplace, but I have seen several products appear, stay awhile, then mysteriously disappear very soon afterwards.  Fortunately, Rendo seems to comply very well with pulling those violations.  But, again, how much of the game is based on legal knowledge.  If you clearly create and distribute content for profit without due permission and license, you will find yourself in more than local hot water.