Why would such an object have trading power? Why would the next guy along want it?
Discussion
If Person A doesnt have food but has Money, he can trade that for Person B who was food and wants Money in exchange.
Why would Person B want the money?
Person B wants food, shelter, companionship, amusement, etc. What does he want "money" for?
(Money in quotation marks because we are imagining it is some intrinsically useless trade token such as fiat or Bitcoin, not commodity money)