The loser supplies all drinks for next year's draft: everyone submits requests in advance, and the loser shops, hauls, and ices the entire order. Requests trend expensive the moment the loser is decided. The commissioner audits the cooler at the door.
Budget note: this is one of the expensive ones. Decide before the season whether the loser pays, the pot pays, or the league splits it, and write that down. Money arguments kill leagues faster than collusion.