Sportsbooks limit winning bettors because a customer who keeps winning is, from the book's side, adverse selection: someone who knows more than the price. A lower maximum stake is the cheapest response. Wikipedia's summary of the research says bookmakers usually detect arbitrage bettors quickly and that their maximum wagers are often cut heavily, sometimes until betting is no longer viable.

We compared that picture with 30 days of our own esports data (Sep 6 – Oct 6, 2026): about 4.87 million arbitrage opportunities across 27 books : 25 sportsbooks and crypto sportsbooks plus the Polymarket and Kalshi exchanges. Three results stand out. Esports arbs are much larger than in the football study that is usually quoted: the median best ROI was 2.89% and only 13.75% of arbs were below 1%. A rule of thumb we have used ourselves, that a 10%+ arb is a stale line, is not supported by the lifetimes.…