A friend sent me a link to a short silent film of Estonian knitters in 1937. Like the Shetland knitters, they knitted shawls fine enough to pass through a wedding ring as well as other items. You can see the traditional Estonian nupps in the finished shawl. I included them when I knitted an Estonian lace scarf in 2004, and they are very fiddly.

It looks to me as though they were being given yarn to use and then paid for the finished goods when they took them back to the supplier. That was the way commercial knitting and weaving was usually organised in the UK back in the days before they became factory-based processes, but it is rare now.