I am basically a comic artist, so I am interested in expressions mostly. That's why I do the beauty and the beast theme a lot. It warrants different expressions, fear, weirdness and shock that you can't put in regular scenes but do well in story telling images.
Well, you could of course, but it would so look terribly out of place that I would not care for it. This March Monstah Month helps to get into different creatures as well. When I do the incidental Monster, I go to werewolf or vampire often, because they're my favourites. Close to humanoids (yes, even the werewolf) and yet menacing enough and diverse enough to keep it interesting. You'll see some of those too in March, I'm sure!