Fuck the wank, I love that theatre. The ones around here don't seem to give a fuck what the previews are. Given, I've yet to see lots of gore like what the OP described before a children's movie, but lots of general violence and sexual content generally come before whatever movie I'm seeing. (And don't even get me started on the commercials they run on TV.) I guess I'd be a terrible parent, because I kind of expect previews to be that way.