We will only get 150 people villages if civilizations collapses, billions die, and humanity turns to subsistence farming. Even among 150 people, there will be trade in goods and favors. People have different talents and skills.

As soon as trade develops between villages, currency becomes extremely useful. There are seasonal goods, especially in agriculture. Sheep are shorn in spring to produce wool, much earlier than harvest for Apples and grain. So if you want to exchange wool for Apples, you need to make a contract or IOU note to deliver Apples in a few months. Now you basically have vouchers for commodities. You can then trade the Apple voucher for new metal shears because you don’t actually want Apples. Suddenly you trade vouchers for vouchers and it becomes a little cumbersome. There’s also always the risk of a voucher not being honored. So the village council decides to issue standardized vouchers that can be redeemed for grain in the community granary. Currency is reinvented because It’s extremely useful.

Anarcho-Primitivism is certainly a romantic ideology.