There are two kinds of jokes in play here:
Joke A: Jews sucks.
Audience A: Haha yeah jews do suck
Joke B: Jews sucks.
Audience B: haha holy shit how can anyone say that with a straight face you're horrible
In Joke A, the target of the joke are the jews. It meant to bring attention to them, and have people laugh at them.
In Joke B, the target of the joke is the joker. It's meant to bring attention to himself, as a horrible person, and make the audience laugh at him.
PDP is Joke A.
South Park is (typically) Joke B.
Joke A: Jews sucks.
Audience A: Haha yeah jews do suck
Joke B: Jews sucks.
Audience B: haha holy shit how can anyone say that with a straight face you're horrible
In Joke A, the target of the joke are the jews. It meant to bring attention to them, and have people laugh at them.
In Joke B, the target of the joke is the joker. It's meant to bring attention to himself, as a horrible person, and make the audience laugh at him.
PDP is Joke A.
South Park is (typically) Joke B.