I have some ideas but I need to have some more details about what you mean.
There are some gambling situations, like tournaments, where the top x% of all players will be paid and of that x%, the payouts are weighted more heavily towards the top place. There are also progressive jackpots where every game that is placed adds value to the jackpot until a winner occurs and then the jackpot resets.
By steepness, do you mean the distribution of the payouts? Like a flat payout or a varying payout? I don't know how you mean "spread" here.