If you look at the ones whose eyes are on the sides of the face you might notice that they are all herbivores, otherwise known as "prey". Having eyes on the side allows them to view much more of the environment, looking out for predators. It gives them a better chance at survival.
Carnivores and omnivores have eyes in the front because it provides depth perception necessary for hunting, and attacking. It's difficult to jump on prey if you can't judge its distance from you.
Just one more piece of proof that in nature, Man was intended to hunt and eat meat to at least some extent. It helps prove that vegetarianism is probably not the best way to go. We need to be what we were created to be - hunters.
Take that, PETA.