With all due respect to my Catholic relatives and friends, there are more important fights out there than the toilet humor of South Park. Besides, ex-Catholic Trey Parker was even more irreverent when mocking the Vatican in the pedophile priest episode.
South Park is only ONE battle out there. Those who largely control the common culture are doing everything they can to discredit the symbols of Christianity. There are ways to attack truly superstitious religious practices, but the authors of South Park have no business even trying. They would not if they didn't know that the powers that be will let them get away with almost anything that serves to discredit religion. But you are not going to see Al Jaz running South Park episodes that deal with Islam.
There is a thread about "Corpus Christi", which unlike South Park demands to be taken seriously and is by the "intelligentsia" who embrace all that is homosexual.