Indy sells a bunch of passes. They keep a % of that total, might be 15. The rest of the money is divided up paid to the resorts based on how many Indy Pass redemptions they get. So the "yield" - revenue per skier day for each ski area - is not determined in advance. The whole system is based on an estimate of how many days on average each passholder redeems. (Those estimates have proven to be pretty accurate.) If every skier went to every ski area on the pass and skied 2 days, it would never work.