Humans commonly find attractive other humans (no offense if anyone likes other things), so we tend to like what look more humanly shaped.
Pixar humans simply don’t look realistic, because their proportions are heavily caricaturized, thus making them less physically attractive to most people.
Then again, most of you are very young, so I suppose it’s normal you have crushes on cars or fish 
Yeah, I think I have crushes on two cars and a human.
I have never had a crush on a car.
Woody is the only non-human Pixar character I’ve ever “crushed” on. And, he is, at the very least, humanoid. And the exhaggerated features is personally why I like Mr. Incredible. His nose, hair, and muscles are perfect!!
I don’t know what to think about Merida yet. She did look pretty awesome in the teaser but I can’t judge her for just that one thing.