I'm of the same opinion when I see the dime a dozen Mercedes or BMW in the middle/middle upper class ends of town. I can understand getting an AMG Merc or M series BMW if you have the money, but the average luxury brand 60 to 80k car that is parked every other parking spot with the owner maxxed out on leverage just seems foolhardy to me.
They're billionaires because they don't waste their money? I don't think so. They're billionaires because they invest in companies that provide shed loads of value to their customers, so their stock is worth more.