But they do; sure, they spend heaps on shit like houses and cars and parties and vacations or whatever other hobbies they have, but most of their money is in their companies, stocks, stock options, tax havens, etc. At some point they reach a critical mass where no matter how much they splurge, they will never see their wealth decline. At best the companies / stocks they own will lose some value, but they will NEVER feel that in their wallet.

And some will set up a charity, but people like Bill Gates have never spent a significant portion of their wealth on that. Again though, that may be a logistical problem - they can't spend money fast enough whilst not splurging it.

Of course, the solution is simple; have the companies pay their staff better. Or give the staff stocks themselves, to be force-bought by the employer when they leave / get fired, and have it pay out dividends monthly to stipend their base income. This gives the employees representation in the board of directors as well, which is much needed in the modern capitalist system.