Indeed, I think the fetish for violence in the US is much more developed than here in Europe. I mean, you have fsk10 films where people are murdering each other, but as soon as one can see a female breast, it's fsk18. It's absurd.
Also, I think one difference is that we (at least we germans/austrians) had to face the dark sides of our history after WW2, while in the US you are still celebrating the native american genocide with thanksgiving.