Yeah thats not good. Without some pretty heavy moderation this kind of thing can never fly. They need to have some approval queue where a person gives a stage the go before letting it out into the wild.
I actually laughed at the Climax one, I thought at worst you'd get things like the 9/11 one, but I didn't consider that the stage builder was robust enough for things like that. But yeah you can report them, so I guess you'll be seeing less of those eventually.