I had a friend who was moving country and wanted to sell his Porche. Someone offered to buy it for a reasonable price, but wanted to pay cash. My friend thought that sounded really dodgy; so he agreed on the condition that they both physically go to a bank teller and have the bank teller deposit the money in his account as he watched. The other guy agreed; so that's what they did. He showed up with a giant bag full of bills, just like the big drug deals in the movies. At that point my friend felt he'd done his duty, and that anything dodgy to be Somebody Else's Problem to detect / deal with.
Afterwards I heard that Travelers prefer dealing in cash; so there wasn't necessarily anything dodgy going on (other than presumably the general effort to avoid scrutiny).
That seems strange.
Some luxury brands intentionally limit production of popular items and only sell them to their best customers. Since everyone wants the limited things, they buy lots of the lower tier, unlimited stuff to become a VIP customer and get offered a slot to buy a limited item. Ferrari is famous for limiting sales of their highest end cars to certain clients. High end hand bag producers limit sales of their most popular models to approved clients only. High end watches are similar as well.
If you can't afford all the extra stuff you had to buy along the way, you can try to resell it and get some of the cash back. If you need more cash, you can resell the limited availability items as well, often for a significant profit over the MSRP, even after the middleman's cut.
Fashionphile, The Real Real, Ann's Fabulous Finds, Yugi's Closet are all active companies in this space.
It's just a weird choice IMO.
I certainly have items that I could sell but don't want to deal with the time actually selling it.
I sold my GPU for $2500 yesterday. Cash please. It's currently lying on my kitchen counter.
Now, piles may be crazier, but sell a Tesla?