That sort of brings up a point that I've noticed about myself. Once I CAN buy something, I usually no longer have the interest in it. No, I can't buy a Gulfstream G700, but I could buy a used Cessna 172 (actually I DID buy - then sell a Cessna 150 when I was a 'kid.') I can't buy a yacht, but I could buy a nice bass boat (back in the day on the mainland) or a nice cruiser or sail boat here where I could (but wouldn't) use it every day.
I could own a sports car as well as my two beaters - but then I'd need to negotiate a parking space in the condo garage. I could afford it, but don't really want it.
I'm guessing that the "rich" (whatever that means) are similar. Why buy it just because you can? Even the "rich" know what they want, what they would use, what would bring them pleasure. Why would the "rich" as a group be any more into possessions than any of us - some of us are and some of us are not (regardless of our financial situation.)
It's not unlikely that many rich folks are happy to just upgrade from PBR to craft beer. Most of the rich probably find a Lambo much more headache than a nice new Town car. I think it's as simple as people are people no matter how much money they have. Some are "fulfilled" by possessions and other are not. Most of what I've heard here is that the rich are just like us - they just have more money.
YMMV