I love it when people declare that they NEVER reload, like it's some sort of badge of honor or something. Who cares? Mostly, I think these are teenagers. I've only reloaded the game a few times, to correct grievous errors, like declaring war on the wrong AI or accidentally gifting cities, but I don't think that makes me any better than a player who habitually reloads whenever he gets an undesired result from a goody hut. That's just silly.
In MP games, you don't have the luxury of reloading, so it's pretty much tough luck. In that circumstance, at least, you can ask the other player to gift you back the city you accidentally gifted him. I can't imagine someone saying no to that. Maybe on Gamespy...
I agree with you about the "I never reload" folks. It's a game for crying outloud. Who cares if you reload?
I personally don't reload following a bad turn of events. I do find it eye opening to load an autosave sometimes to see if I can learn from my mistakes. I especially do this when I move up in difficulty. I recently moved back up to Prince difficulty (I started over at the lower difficulties after upgrading to BTS). I have only played two games on Prince so far. I did not achieve a victory in either one, but one of the games was moderately successful before I saved and exited (I had my entire continent). I have tried each of the games two or three times from the initial autosave to see how different decisions pan out.