From my experience, the screwing people over part is the goal, not the winning. They don't feel superior for winning the game, they feel superior because they were able to mess you up.

My younger boys play some Roboblox game or something like that, with a lot of different servers with various challenges and things, and there are a lot of people on there whose sole goal is to mess everyone else up.

It is like in minecraft going into someone's server and destroying their structures.

Or back in the Everquest days of getting a train of mobs on you and dumping them on an unsuspecting party.

I'm sure there are plenty of other non-diplomacy examples.

The only way we'll know for sure is if we let cheaters come back, make an account, explain their rationale, and then ban them again. I don't know if I like that so much.

The other is to have cheaters come forward, label themselves as such and explain why they feel the need to cheat. I would welcome this.

So it's the anonymous online outlet for the gaming sociopath or misanthrope? I guess it's better that they let it out in a game than in real life...

Well that's a challenge to the argument that games make people violent. In fact that stands to prove that games stop people from becoming violent.

I think there are a few types of cheats.
Some people who are new and metagame with friends don't even think if it as cheating. People form alliances in the game and what could be more natural than allying with your friend.
Playing with a multi is like change the game setting from hard to medium or easy in a computer game. Sure some satisfaction is lost because you are playing on the easy setting, but this is made up for for the satisfaction of winning.
Some players enjoy cheating the system. They are playing two games: diplomacy and cheat the system. They get a buzz in seeing how many multis they can create without getting caught. It's a challenge.
Some players think they have discovered a clever way to win. After all it is Diplomacy and isn't this the game where anything goes.
Some players have ego isssues and are delusional. They know they are cheating but somehow they are able to lie to themselves and convince themselves that they really are a top twenty GR player.
Some players are stupid. I remember one player who couldn't understand what he had done wrong. His excuse was that he was just making his multi play the moves that his ally would have played. What's the difference?

Based on what I've seen as a player and a moderator, I think spyman and Alderian have summed it up pretty well. I would have added my own specific thoughts, but it would probably be only just a more verbose rehashing of what they've already said.

It's about dick size. Evolution made us care about being better than everyone else. It's about dick size, even if you have to make everyone else shrink to look bigger.

I totally get the "meta"s as well. I personally know several users, and I have made it a point to either play a private game with only friends and family, or only play with strangers because it would be too easy to look like you're choosing your alliances based on relations rather than strategy whether it's true our not. That's a far cry from cheating to me, but it's still unfair. I like spyman's rationale, though...delusion may be a big factor.