This goes back to our ancestry. At the very basic level, the primary instinctual urge of a human being is to reproduce. Many of the things we do on a daily basis, even though we don't know it and probably attribute some other meaning are in fact for the sake of one of these three things:
1. Having Sex (The biological urge to reproduce is satisfied even with protection, which is why I don't specifically say "reproduce")
2. Food and Comfort
I don't think entertainment has always been a need..because at one point in history we didn't have much time for entertainment. We couldn't just go to McDonald's. The need for entertainment probably evolved from technological improvements to make the other 2 things easier.
Now that you are probably wondering where I am going with this...
"Politics" is really just a word describing "Diplomatic methods of achieving more power." Most human beings do not necessarily require that power - but the things that power brings...which are the three things listed above.
This is not an explicit rule without exceptions of course. I have to say this because I'm sure I'll get flamed if I don't. Even saying this, I'm sure I'll still get flamed by people trying to put religion or morals into the mix...but those are really just things we use to make ourselves feel better. Some people use their power for other things, such as bloodlust - but if we want to over-complicate it all then we might as well just write a book. So again, my list is basic, instinctual, and not without exception. It is however, *in my opinion*, as accurate as I you can get.