Stamps are not legal tender but have been used for private transactions. When I was a kid, I remember being at the five-and-ten downtown and my mother paid for something with stamps as she did not have enough change. The clerk (the owner) accepted the stamps at face value. In 1974, a penny shortage was alleviated by a run on one cent stamps. I recall the same store made change by giving strips of 1-centers to customers long after that.
Of course, in other countries, emergencies made stamps a currency. I have stamp money from Russia in 1917, when the war demand for copper made coin shortages. In Germany, private firms tucked stamps into their own coupons to give them value as money.
"Cowards & idiots can come along for the ride but they gotta sit in the back seat!"
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