One of Humanitys greatest strengths in my opinion: We dislike death more then any other creature.

so we kill for fun?

He was talking about our own personal deaths. We may kill others if it enhances our chance for survival (money, women, etc.), unless your a psychopath.

 

But the majority of the population don't kill people, because we desire the survival of the species.

so we kill for fun?

 

If you really wish to know why we "kill" I suggest you read Desmond Morris, The Naked Ape and The Human Zoo. Its a simple question you pose, but the answer is very complex. Much killing has to do with re-directed aggression, and animals do it as well when caged.