This is not to say that Anime is merely a collection of Disney-eque films. Anime is far more serious than most American animated film, for in Japan, the Animation industry could be compared to our own Hollywood.
Anime films can certainly be humorous.
One can find entire Anime series with the feel of Saturday morning cartoon humor. Maybe it is because of the massive action possible in Anime. When your principle characters are illustrations, stunts, movements, and fighting scenes no human would ever consider doing become possible. Modern Hollywood studios could perform such tasks with time, but certainly at a cost. It is the same thing w ith models of spacecraft or vehicles.