Just to be clear, Surf Cup didnt invent the practice of making a percent off players staying at specific hotels. It's an industry standard for many different types of youth sports.
Last week I heard of competitive dance teams doing a tournement in florida + parents going through the same issues with hotels.
Tournaments could use their power the other way around, offering hotels the opportunity to get preferred billing on the tournament website if they offer group-rate discounts to teams. And them sell advertising to those hotels along with that.