At the risk of getting totally fried, I think, IMHO, that most people simply comply with the "standard" rules because they either
1) Want to play GOTM, tournament, or have a HOF entry,
and that if corruption in the standard rules was different, they would play that way. Voting for the standard is NOT, I think, necessarily a vote FOR corruption or the way it is done in the game, or a vote that they LIKE it this way.
2) They are confomists and don't feel comfortable changing the rules- that is "cheating". (Now, folks, put down your flamethrowers, it is not necessarily bad to be a conformist. If everyone was a non-comformist ... well, they would all be conforming, wouldn't they??)
Perhaps another poll entry could be: I play standard rules but really wish the corruption there was X % less, where X was 20%, or 30%, or 60%, etc. (Guess that would have to be a couple of entries, eh?)
Personally, I would prefer corruption to be less, say that a totally corrupt city had about 3- 5 shields per turn, maybe up to 8 or so. Not enough to really build military units, but enough so that they could at least decently build some culture/commercial stuff. THis would, perhaps, increase the strength of the non-warmonger approach more then it would help them. (Bill Chen's idea of shield producing specalists could be the easiest way to achieve this without extensive re-working of the game. GREAT idea, Bill!!) The slider approach is good because its easy and allows everyone to adjust it to how they like it. For me, corruption is absolutuly hands down the most frustrating, fun killing aspect of the game.
Finally, I think that corruption should decrease a bit as the world gets "smaller", ie with the development of RR and modern communication stuff (Radio is the obvious tech, also perhaps after enough Airports have been built (now that we can build them, in PTW, that is, also perhaps add "TV" or "News Syndicate"?)
Enough, sorry I rambled. Down with coruption!