Casinos already know that our chances of winning are much smaller than losing. If you win $100 today, you can bet you will lose even more than that the next time you play. That’s why they do everything they can to keep gamblers playing, hoping to chase back their losses. It is a clever trick, and I believe that we all know it already. But we still gamble, driven by the slim hope of hitting it big and becoming an instant millionaire.
In fact, I saw an interview with someone who kept all his lottery tickets, and despite years of playing, he never won, not even once. And guess what? They already spent millions for that.
Actually the main reason for a casino is to entertain their customers but since we already have many greedy gamblers that won't gamble responsibly, so they have little chance of winning more than their losses. However, only few gamblers quite when they are satisfied, but many gambler continues gambling untill they lose everything they have (even though they have won a decent amount previously).
One reason why some gamblers lose bigger money after winning a decent one is probably because we felt that as we have won yesterday we can use that say strategy to win today. But funny enough that winning doesn't work that way.
We have a lot of presumptions about a casino, what they mean we will never know, whether it really makes us happy or not, or purely they do business and give you great expectations, casinos often offer big wins in their advertisements instead of fun gambling experiences, do they write fun in their advertisements, no, they write bonuses and get a certain amount of prizes, until I think that fun is taboo in this context.
But yes as much as gambling tension and greed is definitely there, humans are always dissatisfied with what they have, we have to accept the fact that losing money is a way of gambling to make gamblers aware.