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For example, what if we had a country where currency was canned food.
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Cigarettes in post WWII Europe became a de facto currency in the chaotic aftermath, exactly like your example with canned goods. Didn't matter if you didn't smoke, it was still good as currency to the non-smoker, since you could always exchange with someone who would eventually consume it.
Libertarian thinker Murray Rothbard has an excellent little book about how money went from being backed by gold to being the worthless "fiat" currency it is today.
What has government done to our money?