I'm not trying to turn this into and "us vs. them" situation, because I hate that kind of stuff. Unfortunately many "print" cartoonists use "web cartoonist" as a pejorative, implying that the majority are wannabes and amateurs who can't sell their work to legitimate markets and thus create cartoons for the Internet. Unfortunately, they're mostly right. For every Scott Kurtz or Penny Arcade, there’s a zillion badly drawn and horribly written web cartoons. Web cartoonists can disagree with this and accuse the print cartoonists of being snobs, but it doesn't change the reality of the situation. Don't believe me? Go look at a hundred web cartoons. Go look at a thousand. Go look at a million (because there are at least 6 billion web cartoons currently online). The vast majority are just plain bad.
Web cartoonists are guilty of their own snobbery. They fashion themselves as the creative visionaries of a bold new medium, and sneer at the "boring and mediocre" work of traditional cartoonists. In some respects, they have a point. A lot of print cartooning (especially syndicated comics) is created to appeal to a mass market; it's not particularly innovative. But if you look outside newspaper comics (magazine cartoons, greeting cards), there is a lot of very good stuff being done by traditional cartoonists. It's just as "edgy" and "fresh" as any web comic. And odds are it's drawn a million times better and is much funnier.