Yeah, maybe that's part of the appeal. She looks so sweet and normal; then the stuff that comes out of her mouth...
A weird, out-of-nowhere punch. You want to pat her on the head, then you realize "she might chew my hand off".
I probably need to see it again (and some new, different episodes), when it's not so late and I'm not so loopy. But I'd still find it funny because of her delivery and apparent lack of shame.
Another comedian I like, and who works in a similar vein (quite attractive and "harmless"-looking, but once she opens her mouth and starts talking...yikes!) is Chelsea Handler. I bought her book last summer and it's a riot...worse than any three guys talking in a locker room (and funnier too)!
She had a show on E! a while back that was structured a bit like Dave Chappelle's show: she'd come out on a stage to a small crowd, riff a bit, get a few laughs...but mostly was there to introduce previously-filmed, standalone segments of her doing various things or going places, and often providing subtle wise-ass commentary.