I remember people playing the “Airplane” Ponzi scheme. some claimed to have made thousands. I also remember the Soap scheme, the Worm farm scheme, the EMU scheme, the synthetic OIL scheme...
Several years ago, AARP magazine had an article on how a Ponzi scheme worked and said they all fail. Then they said Social Security was not a Ponzi scheme because it has not failed.
A few pages later, an article by Jane Bryan Quinn in the same magazine showed how the SS system was set up and it was just like a Ponzi scheme.
Worm farm, a scheme!? I now have worms all over the place. But so dam hard to catch! :-)
What I recall of the airplane pyramid scheme scandal was that a boss would get his staff to join it, with pressure, and the lowest employees were coerced last so they’d be the stuck suckers.