If you profit at sports betting they limit your bet size severely

Even if you don’t profit but place what looks like smart bets

A casino or bookmaker doesn't need to heuristically identify betting behaviour that's 'smart'. They don't need to spot evidence that could be hidden by good opsec. No need to find micro-expressions or hidden cheating gadgets. Nor to do background checks to know you've got a buddy with insider knowledge.

All they need to do is check if you're cashing out more chips than you came in with.

It's not trivial for the casino to track this against a determined adversary. If you're already thinking about "good opsec", you can get someone else to help cash out your winnings.

A buddy from out of town, or a losing regular, or a poker player who the casino doesn't care if they win. In Vegas some casinos' chips are negotiable, officially or unofficially, in other casinos.

Exactly - they don’t need to catch you cheating, they just need to decide you’re bad for business

You can just jump bookies.

Except in the state of MA.

They rightfully passed legislation banning such practices. The idea is that if casinos and bookies refuse to cap your downside, they have zero right to cap your upside.

Not everywhere. Circa wants winners.

Sports betting is the one place that "prediction markets" make the most sense. Instead of there being a house to win against, the market just skims a fee. The line is set organically by betters, not be the house targeting a profit margin, and the house has no incentive to restrict successful betters because they solely profit on flow, not losses.

You do have to be careful to avoid letting whales manipulate the perceived market. There are ways to con other gamblers with carefully timed bets.

The bigger the market the harder that is, so maybe it doesn't apply at the level of online sports betting. But organized crime could make trouble at horse tracks.

How would that work?

Lots of bets on horse A. Makes the odds on horse B look cheap. Place late bets on B.

It helps if you can also rig the race, but just knowing the odds better than the pari-mutuel stakes gives you an advantage.

But if it's parimutuel, don't you lost more on A than you can make on B? Are you tricking other players, or is the idea that you make lots of bets on A, and then make bets on B fast enough that the bookmaker does not have time to correct?

What about Frank Rosenthal? Admittedly these guys are extremely rare, that's why the handful of successful ones are famous.

Never heard of him

The movie Casino was loosely based on him. Worth a watch, but also actually looking the real guy up.

Tony Bloom, the billionaire owner of Brighton & Hove Albion FC seems to be managing it.

https://www.theguardian.com/football/2025/dec/05/brighton-ow...

Tony is also super smart in how he gambled. Your average degenerate is nowhere near as intelligent as Tony is.

I have a very small edge in sports betting although I don't really do any of the deep overpriced/underpriced arbitrage or any special types of bets outside of wins/loses. And it's limited to tennis, a sport I've played my entire life and have followed the pro circuit closely for 3 decades. And even then my edge is very small, and the strategy I use when I do bet doesn't make me much in total return.

We all have the occasional friend that brags about every time he wins money at the casino. If you accompany them a few times, it’s incredible how the “always winning” story just changes.

I used to work for a sports betting company. These people definitely exist. They are few though because they are the ones who understand that the sport/game/match/whatever is irrelevant. They bet the "odd line". They bet on the platform that screwed up and didn't adjust their line quickly enough to follow the market. They don't know baseball, or football, or tennis. They just know the numbers.