Earlier quoted context omitted.
I really don't understand how people get greedy after earning that much money. Is it just the high/excitement the comes from it? Seems like money would no longer be motivating.
Many people around the world would say the same thing about the lifestyle enjoyed by the average commenter on this forum, but most of us don't think of our incomes that way. The average American does not need to live in the home size that has become desirable; they do it because they can. You can't set an arbitrary limit on when money ceases to be motivating. At $100M in net worth, you no longer need to compromise on…
This really isn't true. Middle-class Americans who don't make enough money to sustain their current situation are at significant risk: 1) they can lose their ability to keep paying their mortgage, and then lose their home to foreclosure, or their car to repossession. Their car is what enables their lifestyle, their career, etc. Their home is where they live. They could downsize some of this stuff, but only so much: if you go too cheap on housing, you're now living in a bad neighborhood, which can be extremely dangerous. If you don't have enough money for good health insurance, your health is now at risk. Medicaid usually isn't available to poor adults who are able-bodied, and many healthcare providers refuse to accept it.
There's a reason many people have as their long-term goal to pay off their house ASAP, and to get out of debt, because that means that they're now in a position to afford their current lifestyle but with a significantly lower income, which reduces their risk immensely.
People who are millionaires and up do not have these concerns in the slightest. Going from a $20M mansion to a $750K house is not going to affect your personal safety in the slightest, but going from that to a $500 house in Detroit definitely will.