Next time you're in the casino, do the math.
I think here is the problem. He can't do the math.
As you have said casinos know exactly how much they are going to make on everything. If you walk through vegas you will see slots that advertise 95% payback. If I win $100 then there are going to be a lot of people losing a couple dollars here and there. There will also be people losing more. The odds are programmed into the machines. You can also figure out the odds for table games too.
His argument that the casinos have to keep people playing long enough to do something stupid is ludicrous. Yes , casinos do hope people bet stupidly but they cannot rely on that. They can rely on probability.
The first sign he was talking out his ass was when he claimed to have never have lost money in being to casinos hundreds of times. If people could win consistently in casinos they wouldn't call it gambling, they would call it winning and there would be no casinos.
You are correct in that psychology gets the mark into the casino, but the odds is what makes them the money.
Do you think he can understand how casinos make money on sports betting? Maybe he needs to take a lesson from a bookie.
Facts don't lie or have an agenda. Facts are just facts
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