I'm assuming I'm purchasing/selling a lot of MtG/Funko here in this example.
For big transactions where something of actual value is exchanged, both parties will want an escrow, and this is where a public exchange comes in.
I have heard from friends who are in these countries observing transactions that go into the millions of dollars that are being cashed out (not even laundered) like it's just another day. Nobody asks questions, nobody cares either and if you bring it up you will likely lose your job in few months or so.
Escrow companies open and close all the time for this very reason. People wash money alllll day long with US real estate for this reason.