He could say, go race a stock car, have about as much fun, and fund 20 startups as an angel investor. Instead, he's blowing his money on expensive thrills.
Besides - why the heck should a private guy have to do anything of social value with his money? What, you want him to fund your startup with his hard-earned cash? Why should he?
There is nothing that says an entrepreneur has to spend their wealth investing in startups. Tom Perkins commissioned the Maltese Falcon, Larry Ellison (co)owns The Rising Sun, Elon Musk founded a freaking space-ship company because he wanted to.
This: "Instead, he's blowing his money on expensive thrills."
Why shouldn't he? It's his money, he's not harming anyone by doing it, is he? Owning an expensive car doesn't mean you do anything illegal or immoral with it.