They've opened Pandora's Box. Schools can try to control some variables contractually-- and they are-- but really, how and who enforces it? And then there's accountability. What if a player is contracted to do a scheduled event and they have class or the coach calls practice or a team meeting? Schools want to be hands-off and coaches don't want to work around player deals. Teenage SAs aren't businesspeople, and their days are already full with school and sports. If it becomes de facto gifting, it's really just putting a wildly inflated price tag on yesterday's closet strategy. The only schools that want that are the ones prepared to capitalize on it.
And yes, it can be a setup for friction. The get-nothings are going to feel unappreciated, the get-a-littles aren't going to be happy with that for long and the get-mores will want more and more and more-- and threaten to portal if they don't get what they think they can get elsewhere. Not only are schools having to recruit new players, they're having to continually rerecruit existing players and invest a lot of time and money in keeping players monetarily content and teams cohesive. We're already seeing it.
It's difficult to contract, difficult to enforce, difficult to manage and difficult to maintain. It'll have to evolve-- and it will.