Additionally, their spending creates income for other people. For example, a carpenter I knew worked for a while in Aspen, Colorado. A wealthy woman wanted a skylight put in the foyer of her home, and he told her that the location she wanted it in would not create the lighting effect that she wanted. She insisted, and he was right. So she next paid him to remove it, repair the roof and ceiling, and put it where he had originally suggested. Most of us on this forum would consider that a foolish waste of money, but to her it was pocket change, like most here would buy a candy bar. The effect was that it kept him employed for a week instead of a few days, and in turn his spending on materials, tools, food, etc. contributed to giving other people jobs.
I think "wealth" is a relative term. Relative to someone starving in a tin shack in Africa, DW and I are astonishingly wealthy. We have a nice home, two-car garage, a five-year-old pickup truck and five-year-old car, everything is paid for and we don't give a thought to how to pay for next week's groceries. But we can't afford some luxuries that others take for granted, like a new Caddy every year or annual round-the-world cruise - and yes, some people can do that and pay cash.
Whether wealthy people bank their money, invest it, or spend it, that also creates jobs for other people. When someone goes to the bank for a loan, where does the bank get the money? From others who banked their excess money. We have several savings/investment accounts, but that money is not sitting in a drawer somewhere, it's being loaned out to others. The bank charges them a higher interest rate than they pay us and the difference, after the bank's expenses, is the bank's profit, some of which goes to individual people who invested in the bank as shareholders.
Think of the scene in It's a Wonderful Life where the S&L is down to it's last two dollars. All of the other depositor's money was not in the S&L, most of it was being loaned out to other people. So if wealthy people want to spend their money on whatever suits them, fine! They want a 300 foot ocean going yacht, then fine - that's going to give a whole crew of people jobs because someone has to build it, and another crew to maintain it.
It's the people who are not wealthy but try to behave like they were that create problems for themselves. At work we called them "29-cent millionaires".