If I owe someone a small amount of money, I sometimes suggest tossing a coin: With a 50% chance we just both forget about the debt, otherwise, we double the debt. The expected money stays the same, the variance is insignificant as the amount is small and with a 50% chance, we do not need to make the hassle of exchanging coins. However, it seems that a lot of people are unwilling to do money betting. Even with amounts less than 10 Euro.
Another possible advantage of lotteries: You simply need to put in less work in decision-making. For example in the donor lottery: https://app.effectivealtruism.org/lotteries