Most audiences like to avoid certain subjects, rape, torture, extreme cruelty and such, or at least when they're grounded on some level with reality. When the average mainstream audience member does venture to such subject matter, they like to be handed a pretty simple message they can walk away with, nothing to much more complicated than "atrocious behavior is atrocious". Something like that. The better examples will have some more complicated subtext, but the mainstream audience will be clearly handed the message they need.
I think it's one of the reasons David Lynch sits so boldly way up some people's butt. There's nothing in his text to suggest he endorses antisocial behavior, and certainly the things he says outside of his work suggests a gentle and kind soul.
Yet his movies contain a great deal of atrocious violence and cruelty, and without any single obvious answer at all, even less a specific denouncement by the text of the film of the characters behavior. The audience is left to contemplate the actions they've seen, often for a great deal of time afterward. To my mind, this is one of the great potentials of art.
I have a similar feeling after watching Star of David: Beauty Hunting by the great Norifumi Suzuki.
It's about a man born out of the rape of his mother, while her husband watches on. Raised by the husband, a successful businessman, who struggles throughout his life to deal with his own rage as it manifests itself toward the young boy, and the changes the boy himself makes once he reaches adulthood, and how his heredity and/or environment shaped him and his attempts to shape others.
There seems more a tendency in my mind to want to compare this more to Henry: Portrait of a Serial Killer or Man Bites Dog. There's something to those stripped-down look at the horrors of modern life.
But then like Lynch or perhaps The Marquis de Sade, I'm unsure Suzuki wants us to take his ideas entirely literally. Their extremity may be partly to force our reaction - and, in some places even to titillate us - but I see them as about something more simple about how all of our relationships shape us and how we shape them.
For what it's worth, while I'm still deeply in consideration about what those conclusions represent generally, I am sure none of them are positive. And I'm pretty sure a good deal of them have a lot of merit.