I actually think a much bigger deal is being made about this than need be.
It is just South Park.
From what it sounds like, the episode didn't even focus on him, just included him.

The argument was made that kids will end up watching because it is a cartoon (which I personally disagree with, but that is another matter).
But is this really any worse than other material out there?
Especially around Halloween?
How many cult/massacre/monster/horror movies circulate this time of year.
What about RHPS?
Is that any more appropriate?
As parents we should be more of a factor in the shaping our our children than TV is (or video games, or movies, etc.).

Sorry, but I just can't get worked up over this...