Ten people are stuck on a lifeboat after their ship sank. It will be weeks before anyone finds them, and they're out of food.

They've heard this story before, so they decide to turn to cannibalism sooner rather than later. They agree to draw lots to determine the victim. Just as the first person is reaching for the lots, Albert shouts out "WAIT LET'S ALL KILL AND EAT BOB!"

They agree to do this instead of drawing lots. This is obvious, right? For nine out of ten people, it's a better deal. For nine out of ten people, it brings their chance of death from 1/10 to 0. Bob's against it, of course, but he's outvoted. The nine others overpower Bob and eat him.

Something about this surprises me.

https://www.astralcodexten.com/p/lifeboat-games-and-backscratchers