Essentially it boils down to attaching the value of the dollar to a finite resource, and avoiding the perils of inflation due to the government printing more dollars whenever it wants to.
monkmith posted... i've always found it funny that end of the world preppers buy into it, like its going to be useful for bartering in a world where society breaks down and basic resource scarcity is a thing. what the fuck am i going to do with a handful of gold coins and why would i trade my precious food stores for it?
There are other scenarios besides end of the world. If just your country and its currency collapses, gold will still retain its value as a replacement currency or even if you just leave to a functional one.