Good question. Typically it's been exchanges who create th…

Good question. Typically it's been exchanges who create the commodity and the market for it.

West Texas Intermediate Light Sweet Crude, the NYMEX (now ICE), for example.

"one of the world's most liquid oil commodities in an electronic marketplace. The contract…"

Notice the word CONTRACT, as in legally binding contract.

See some of the rules:
https://www.theice.com/products/213/WTI-Crude-Futuresem

Now, imagine a trading entity or supplier who tries to game the system by delivering oil which doesn't meet the specifications due to some wrinkle. What do you think ICE would do when a buyer of WTI doesn't get delivery of actual oil?