Matt Harwood analyzed this question very well - in my opinion - a few months back. I can only summarize - but there is a large class of millionaires in the US, and Europe, Asia (China). I believe he mentioned that there are people making interest earnings in a given period of time that make these purchases seem like a modest $20 transaction for us.
If you have a net worth of $10 million, and your house is paid off, and live a cash existence, then perhaps you have $8 million to invest annually and from that you make 8% Annual interest income, that alone is $640,000. This is a simplistic example I agree, but I will be getting a cash out on a $50,000 investment in late May and I have been mulling purchasing one of a couple saved cars I have on facebook marketplace for $9,000 to $10,000, and my initial investment would not be touched.
Different scale of course, but similar dynamics.