Of course South Park can do ANYTHING filthy and crude but that's okay since Matt Parker and Trey Stowe practically own Comedy Central
I doubt TV Funhouse was canceled because it was too filthy and crude, but that it just didn't bring in the ratings/sponsors. Trey and Matt don't get to do anything they want... "That's My Bush" was canceled because it was too expensive to produce. CC is a pretty small network, and can't really sink money into a show that isn't going to make them anything.
TV Funhouse is never going to attract millions of viewers.