Star athletes are splitting over sports betting money, and the fight is drawing attention to how fast prediction markets are pulling ordinary people into debt.

• Victor Wembanyama said he will never sign with a betting company, calling it shameful; Kylian Mbappé has taken the same line.
• Kevin Durant, fresh off a FanDuel deal, brushed off the criticism as the nature of the business, and LeBron James now has a Polymarket deal worth a reported $15 million a year.
• NBA rules let players hold small stakes in betting and prediction-market companies, which sits awkwardly while several states sue those firms for running illegal gambling.
• The NFL has asked Kalshi and Polymarket to pull player-prop markets it says are easy to manipulate, and both refused.
• Most betting profit comes from a small slice of addicted customers, and Kalshi is now asking regulators to let traders bet with borrowed money.

Outlook: With betting effectively legal nationwide and Congress unwilling to pass a national self-exclusion list, expect more bankruptcies, lawsuits, and pressure on the leagues to tighten their own rules.