As I said, only because he happened to be of some super-species that OWNS humans.
But, c'mon, you're comparing a
human with a
non-human. Humans are naturally weak and slow, it's no compeition only BECAUSE Superman has a natural strength that was not granted to him through any skill or hardwork on his own part. It's like comparing a Zealot to a Zergling; the Zergling has no super-advanced technology, an un-fair advantage. Strip the Zealot down(which would be like turning Superman into a human) would allow the Zergling to pwnzor him,
And yes, you would require some kind of freak-accident for a spider-bite to give you super-human powers. Lots of people have been bit by spiders before, but they've never been granted wall-climbing abilities and super-human athletic capabilities.
QUOTE
Batman has no natural powers,
You just said yourself right there that Batman doesn't have that huge advantage.
BAtman uses his mind and his hard-earned super-in-shape body to kick-ass.
Superman uses his not-at-all-earned body to kick-ass.
If you stripped them down of gadgets, AND made Superman a normal human, Batman would pwnzor Super in a few seconds.
Try to be fair when comparing super-heroes. Batman's the most realistic, and he can kick the

out of his sometimes un-realisticly powerful enemies. THAT's a cool super-hero, Pine.
Wow, I'm ranting in defense of Batman, when I don't even like comics. Rofl...