[strstr]

Zero-sum assumption and lack of returns on bets seem suspicious.

Betting is a bad deal for everyone in this model (even the rich person) since each coin flip is variance for no expected gain. Kelly betting implies you should bet nothing in this game.

[lozenge]

If you increase the payoff of the bet, it might prevent the poorest from becoming destitute, but the relative effect (where wealth concentrates in a few people) intuitively would still be present.

[flawn]

That's what I meant. It just comes down to the inequality being there and rich people having more capital to bet/invest/whatever and relatively get richer just though them having a bigger starting capital.