Hazard.

[M1NISH]

This sounds like great idea, but I'm afraid it could be easily exploitable. Some players could actually lose races on purpose to give their friends good chunks of money. On the other hand, that could make some pretty interesting highstakes racing.

Way number 1. Limit max bet amount and repeat time of this type race, I don't see actually problem in this if amounts of money aren't so big.
Way number 2. There are no other ways hehe xd