I've a friend of mine who always complain that ever since he started gambling he haven't won a good amount, instead he'll be winning less money than what he expected but he can't stop.
People who gamble and continue losing, but they do not give up on gambling all is because they have hope that one day they will win. No time will a gambler gamble without no hope of winning. So, anything you have hope for, you will hardly give up on it. If any gambler believes they have no probability of winning, they will surely not gamble. It is confidence that always makes gamblers continue gambling. In fact, sometimes, even if they want to give up, the hope that one day they will win keeps them going. They always think that if they stop gambling, they might miss an opportunity.
True, it could be that they are in the stage of chasing losses so they continue to gamble even though it turns out that their hopes have never been achieved, and this happens because from the beginning they are typical gamblers who cannot accept the fact of defeat which should be in that situation they take a break from gambling first and resume gambling when there is no longer a grudge against the previous defeat, but what happens as we see that they continue to continue gambling which I am sure that all the decisions and actions they take at that time are based on emotion and curiosity. And the other thing is that yes it is true as you said that if indeed the casino does not provide winning opportunities in every game then logically there will certainly not be many people gambling or maybe even no one is involved in gambling. This means that the chances of winning in gambling are a strong reason about why many people come to gamble.