It's only "shocking" if you let yourself be shocked by it. I've seen enough bare asses in my life that seeing another one doesn't immediately force me to start going insane and objectifying women and tearing down the moral fabric of society. I really don't see the point behind making a stigma out of showing certain parts of the human body. It is just another beautiful creation of Mother Nature. So what if there isn't an artificial piece of fabric between that butt and the camera? How is that offensive?