You mentioned at the end that none of the playtesters split evenly - perhaps this was because (I assume) they weren't playing for real cash, and so screwing people over makes much more sense and has much lower real-world consequences, whereas with the actual thing the contestants wanted to maximise overall profit rather than individual gain.,(reply>), They played for a smaller amount of real money. The "guaranteed 20%" strategy didn't come up in playtesting is because no one else had thought of doing it that way.,(reply>), And yet another factor: they all knew each other and would likely see each other again in the future!,(reply>), There's one more factor: the game carried a prize much more valuable than the $10k pool. All participants are youtubers, and the game is broadcast to a huge audience of a youtuber much more popular than any of them. Massive channel growth, and continued profits for many years to come, totaling much more than the $5k, $6k, $10k, whatever you win in cash. And to win <b>that</b> prize you have to appear smart, funny, likable, interesting, worth following. Appearing likeable was more important than winning.