Liar-Liar Competition and Cold Winters

 You're stuck inside all winter with nothing to do but scam the others into giving up part of their share of the grain. The only defence they have is being a better scammer than you are. The worst scammers give up so much they accidentally let themselves starve to death. 

 In permanently cold places like the arctic, the population never rises much above what can sustained by harvesting while it's frozen. The logical distance between hunter and table never grows long enough for scams to be viable. If someone asks for more food they'll be told to hunt it themselves, regardless of how clever their reasons are. "Bro, you're not my wife, thank god. Did you lose your spear? It's over there."

 Let's say winter is exactly six months. You can trick someone so they only keep five months worth of grain, and they'll have no idea until they suddenly find themselves running out at month 4.5. You can say, "Sorry mate, I can't rush the growing season." If you manage to trick enough folk, you can say stuff like, "It's hard for everyone." If a seal hunter is tricked out of their stores, it's only a week or two, and they can immediately demand restitution from the scammer. The scam is not existentially rewarding. 

 

 Notably only Communists can scam each other out of grain. If you're not Communist you just let the bad farmers starve to death. Sad, but necessary. Without the norm of irresponsibly sharing harvests, it can't be normal to share too much of your harvest. ("Pay me or GTFO.") The scams are only possible because you already fucked up. Maybe a real society even executes the bad farmers early so they don't waste their stores trying to stave off the inevitable. "Scam this." *chunk*

 

 Basically in real life the ant feeds the grasshopper all the time. Bonus: exactly because the grasshopper is a bad farmer, they have poor stores and can make heartrending appeals. Don't work at work, work at tricking someone else into working for you. Hard for the ant, flush with the harvest, to argue that he needs handouts. Irresponsible societies actively punish the industrious for being productive - it's the ant who finds they don't have enough at the end of the hard season. And then you get modernity. And, previously, places like Greece.

 They do make IQ go up, apparently. Liar-liar competition, may the sharpest con win...