Well... there is a drastic difference in anime that is marketed to kids, and what is marketed to adults as serious entertainment.
Watch just about anything by Hayao Miyazaki, and you'll get what I mean - Nausicaä (Valley of the Wind), The Castle of Cagliostro, Princess Mononoke, Spirited Away... They're almost universally ranked up with there with some of the finest American films. Add to that films by other directors, like Graveyard of the Fireflies (which, from what I've read, will put even the hardiest soul under the couch and sobbing) and other, serious adult films (Appleseed, for instance, which I've posted scenes from before), and you don't get the seriously wonky eyes, the comedic background effects, and all the other whatnot that tend to drive away the American viewer.
Much like American animation, there are sometimes you can only achieve your artistic goal by using animation - whether hand drawn or CGI.