I remember having a laugh with my equivalent (Head of Compliance etc) at the big French exchange, then called MATIF, when he said that their Le Havre delivery potato futures contract represented < 0.01% of MATIF trading volume and > 80% of his problems.

That rang a bell, because the UK potato contract, then on the Baltic Exchange, was essentially a game of 'chicken' between two different cabals/shooting parties of UK potato farmers.

"Any economic unit can emit money. The serious problem is to get it accepted" Hyman Minsky