The movie's Spedler mentioned, Shieldler's list and Private Ryan are a good example  for my points - yes, they include violence, but they are rated R, if people dont want to see that, they dont have to. These movies have a message they present reality. If at all possible, people should go and see it. Perhaps humanity will learn from its past horrific mistakes.  A bloody clown/vampire/person to promote sales - no, that isnt worth the shock.
Shawn of the dead - I know some find it funny, I find it repulsive. I'd defend the right of the makers to make it, and your right to watch it, but only if I can make a decision not to watch it.
The image in the banner may be entertainment for some, it's offensive to others. We all should be able to make a choice whether to watch it or not.

"I paint that which comes from the imagination or from dreams, or from an unconscious drive. I photograph the things that I do not wish to paint, the things which already have an existence."
Man Ray, modernist painter
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