My compliments to the artist for maintaining good humor and staying reasonable throughout this rather odd convo.
All these issues are relevant and worth discussing but I can't really understand what it is about this particular poster or artist that would make either the target of anyone's ire. It is what it is, nobody ever represented it as being something other than that...there's nothing sketchy or unethical going on... and here it is, in an open-source public archive, right where it should be.
Of course I think that my own poster I did for The Meaningless Molecules, playing at Divey's at the corner of 437th & Nowhere, that I screenprinted and taped up on the street myself, is much cooler than this. But that's entirely subjective, and I have no beef with my aforementioned poster coexisting with this one on the GP.