They may need the money for gambling, but they are not greedy or desperate to get money from it. Rich people already have money, and if they gamble and lose, they can easily stop and come back another day. One thing about people who don't have money is the way they reason about it.
Anything they understand can give them money; they believe they can make a good amount of money before taking a rest. For someone who doesn't have money, they are ready to gamble to ensure more money is gained from it, but it doesn't work that way. Most people don't understand gambling the way rich people do.
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.