Well, IMHO if you are rich it is stupid to not use your wealth. What is the purpose of it if not use it for whatever reason? Happiness isn't the only one and doing some research for something so individual as happiness is irelevant at all. You can use wealth for example for making life easier, more comfortable or just for aesthetical purpose.

Lets say I am very rich and have comfortable house which is a piece of architectonical art. I would like to go to holiday but I really hate hotels. Because of I can afford the same comfort as at home, I will simply buy a new house at my holiday destination. As years passed, I've collected a few houses all around the world.