It sure as hell works better than bartering. With bartering, you can't always get what you want/need due to you perhaps not having what the person who has what you want wants. Perhaps it would work if you changed items into something universal. Maybe instead of taking an deer skin to the grocery store, you brought it to a bank of some sort and exchanged it for something of universal worth that everyone would accept.
There IS a uniform currency - in a way. In the same way that one bear skin is worth 5 rabbit skins. It's called the exchange rate. Although it isn't exactly a currency you can use - it's an abstract one - it is still universal.
We did this at almost every restaurant I used to manage. It was fair as we ate for free, so we we weren't costing the company anything. Well maybe not for the Mexican place in Louisiana that used to trade margarita's for food at our place. They Definitely lost out on that deal...
Currency or a trade medium is essential to a large economy. Where everything derails is wall street speculations, stock trade, and government sanctioned racketeering better known as inflation.
I used to work at a old timey candy/soda store at an outdoor mall, we used to trade Cheerwine to the gourmet cupcake girl for free cupcakes highlight of my life
Pssshhhttt...what am I saying? They're not even paying for the goods that they're taking from their employer.