South Park is definitely much deeper than that. And maybe the swearing isn't everybody's taste, but it's part of the humor. They use it in a very specific way so it's not just gratuitious.
This is what worries me, looking down on and sometimes even censoring shows simply because they have an edge, even if they are intelligent and have good messages. Just because a show doesn't have cursing, doesn't mean it's any more intelligent or moral.
I guess what I'm saying is, don't judge a book by its cover, nice or edgy.
I mean you can just as easily ask why Sesame Street and Muppet Show needed to include monsters. They did it to prove that seemingly unpleasant things can sometimes be wonderful. That's the point of the
Frog Prince story, and that song from Muppet Show "Frog Kissing":
"There's a happy ever after land,
Deep in the heart of man,
Where a prince or princess abides.
But all we catch are glimpses
Of the handsome prince or princess
'cause they're covered by a green warty hide.
And though they're full of life's potential,
They're lackin' one essential,
To enable them to shine like a star.
And that's for some special guy or missus,
To smother them with kisses,
And to love 'em while they're just like they are.
And that's the secret of frog-kissin',
And you can do it too if you just listen.
Just slow down, turn around,
Bend down and kiss you a frog."