Most economies use representative currency. In many places, notes and coins are largely worthless.
Cryptocurrencies differ mainly by being virtual. Given that notes are usually used to represent the larger sums of money, the virtual aspect becomes mostly semantic. Given that most people store their money in banks, who don't have all that money on hand at any point in time (hence why they collapse), then the virtual factor begins to matter even less.
I don't use bitcoin (or equivalent) for pragmatic reasons. Your point however seems to be about its collective abstraction. If you were being consistent, you would have to be against most mainstream currencies as well. This is not a pragmatic or scalable method of commerce. It very quickly become tedious to trade with items that are of only concrete, immediate value to both parties. Try to imagine how online purchases, or warehouses, would function. There's a good reason why virtually every civilisation swapped to representative currency after reaching a certain size.
