If I understand what you say, a rich person's personality changes a lot and their visions of what they want change too, and casinos and games of chance are something they can easily lose money in , and they don't like that fact, so they Prefer not to take it as seriously as others, because they don't have the need to make money , they just want to make their money grow and not lose it, that's their mentality.
If a person is rich, it means they have found a way to make money differently, I suspect it is some successful business or profitable investments. In other words, if a person is smart enough to earn a lot of money in a different, less risky way, then of course they will focus their efforts and attention on what brings them that money. Gambling might not even be interesting for a rich person.
Maybe they will try playing just out of curiosity, but if it does not work out, they will quickly give it up. Rich people think in terms of money and are very good at assessing risks. That is why such a risky and complicated way as gambling is something they will most likely just exclude from their lives.
"There is no millionaire, who does not want to be a billionaire." Rich people are not different from poor people. I dont have statistics, but I believe that rich people also want to get even more rich in a shorter period, like poor people. There is always other side of the coin, being rich not always means gambling for fun or for curiosity. It could also mean having larger deposit or more chances to deposit more. All people are the same and fall of victim of 7 deadly sins, such as greed, pride, gluttony and envy, all of them are widely presented and found in gambling.