I know of a guy out here that owns a 911 and a 6 series BMW, both new models, and they more than pay for themselves with Turo. He just drives the car that isn't rented or Ubers if they both are.
So it's a matter perspective. Maybe you wouldn't buy a rental car for yourself but if someone told you you could drive a new 911 for free 20 days out of the month and maybe be cash flow positive on it to boot, would you do it then? I would.
It's the difference between not having a 911 at all or having one that I have to share with people 33% of the time but that I pay nothing for. I'll take a free rental car over no car at all.