But I think the most fundamental reason is because, like all art, I like seeing what the human race is capable of when they aren't off killing people or arguing over trivial matters such as politics.
Yeah, I'm a pessimist.
I presume you believe the evil in this world outweighs the good, right? That would make me an optimist for believing there is always some good, or at least hope, in all matters.
I, like the Athenians did, "regard a man who takes no interest in public affairs, not as harmless, but as a useless character..." (Pericles, 431 B.C.E., Funeral Oration). But don't let my opinion on politics, which is perhaps superfluous in this discussion, turn into some sort of political debate. The point I'm trying to stress here is that I, in contrast to your interests as it seems, like to see what the human race is capable of as far as politics and history goes. Hence, I enjoy historical/philisophical/political treatises just as much as fiction, if not more.
I fear I have gone too far in expressing my opinion.