Do you not get at least a little disturbed when you read or hear about the deaths of other human beings that you've never seen? It's not that much of a stretch to apply a certain degree of empathy to animals as well.

Killing animals for food is totally acceptable to me. We're at the top of the food chain, and, let's face it, some animals are both nutritious and delicious. (I strongly suspect that our own domestic cats would probably kill and eat us if they could.) Killing animals as a recreational hunter is a bit less acceptable in my book, but I can see that there may be social and environmental benefits to the practice. Running down animals in your car just because you enjoy killing things more vulnerable than yourself is pathological, and such people should be denied access to cars, guns, or even pocket knives until they've undergone some serious counseling. There's something seriously wrong with people who intentionally kill or maim animals just because they think it's fun, and I certainly don't want to share the road with them.