THIS.
I disagree with this for the mere reason that Jhonen Vasquez just has a sadistic sense of humor, and that was actually him toning it down. I highly doubt he was trying to get attention, considering he's very disturbed by the fanbase he's earned already.
Some real examples? A high percentage of adult swim cartoons. Yes, I like Superjail, which is immensely violent and people could argue that it may seem forced. But in its defense, it has yet to be obnoxious about its verbal jokes, as many shows do. Aqua Teen Hunger Force was a mere TV-PG when it first started and is now TV-MA. Now THAT'S a good example of trying to garner attention by being 'edgy'.
Agreed. Flapjack is more like Ren and Stimpy and Billy and Mandy, if anything. As for Chowder, I can see its Spongebob influences as well as its Billy and Mandy ones, but to be fair that's only because the creator was... oh gee, I don't know, part of the crew for both shows.