What is your opinion on the subject of "money & happiness"?
Interesting study in the OP, but too conventional.
IMO the people who are not happy with nothing won't be happy with everything neither. Yesterday I went for a walk with a friend of mine
when suddenly an old indigent with some Gandalf beard appeared on a rusty bike, with his dog running full throttle, and Deep Purple max volume. You can imagine the scene, epic.
I don't think many people on a Ferrari and a bimbo would be much happier than him. Somebody should measure it scientifically but I would be surprised if the man in the expensive car won. Happiness is subjective and with the proper self control I think that you can modulate it, even when consumer society has teached us otherwise for decades.
Because, in reality, we all have different preferences, and each person is unique, there is no such thing as a universal definition of happiness; it is highly subjective. Not everyone needs expensive things to be happy; we all have our own tastes, experiences, and lives; some of us are already content with what we have and can enjoy life with it. We can't really compare each individual's happiness, which is one of the aspects we differ from one another. I want money but money doesn't make happiness, the only reason why I like money is that it's the pathway to reach my true happiness.