Here's a quick thought experiment. If you give $1 to everyone in the world, and if everyone uses that money over and over to play a double-or-nothing game, you

Here's a quick thought experiment. If you give $1 to everyone in the world, and if everyone uses that money over and over to play a double-or-nothing game, you will end up with around eight billionaires in expectation who did nothing but gamble with their money. Now, you start with people with a million dollars, and all of a sudden you can reach eight billionaires with far fewer gamblers (proportionally fewer, in fact). So, given sufficient gambling tendency among millionaires, you will definitely find a handful of quite rich billionaires whose only skill is (1) being born rich, (2) getting lucky on the gambles.