Seriously I've seen darker stuff in more mainstream films. Certainly we've seen more graphic and gratuitous violence than Nolan's trilogy.
Seeing those side-by-side Schumacher/Nolan clips is certainly an eye opener.
I know that there are more serious things out there than the Nolan movies. I just like to have my superhero movies have a little fun in them and the Nolan Batman movies, while very good, have been a bit joyless.