About your link, its an interesting study of causation vs correlation. Does too much money really make you more stingy or is being stingy how you got that much

About your link, its an interesting study of causation vs correlation. Does too much money really make you more stingy or is being stingy how you got that much money in the first place? Does too much money make you difficult to satisfy or is it because you are difficult to satisfy that you pursue more money? etc.