Very simple. When you get to the wealth levels these fuckers are at - you can buy literally anything. Life gets very fucking boring if you can have anything and everything, and there's only so much travel, material goods and real estate you can purchase before you get bored. So, to cure that boredom, they start being more and more depraved, chasing that next 'dopamine hit'.
For the regular folk, it means shelling out for a nice meal, a holiday or a car. For them - they already have everything, so it comes down to more power over others.