[saghm]

> Speaking for myself, beyond a certain income threshold there has been no substantial quality of life improvement.

I strongly agree with this mindset, and I'd argue that it's pretty well-supported as a phenomenon for most people, if not all. Money is a huge deal up to the point where you can live comfortably and without worrying about the future; beyond that, it doesn't really seem to make anyone happier. That being said, it's still a luxury that isn't at all common for most people, but it doesn't require being a millionaire (at least, not with the current level of inflation).