I guess that is only because it was at first limited to Tallinn and even after the extension to all of Estonia you still have foreigners not covering the costs

I guess that is only because it was at first limited to Tallinn and even after the extension to all of Estonia you still have foreigners not covering the costs with their tax payments. I have no idea what fraction of the people would fall into the respective categories but I would guess that after the extension to the entire nation it is not really worth the effort and costs to make foreigners pay because they are a small fraction compared to the costs of maintaining a payment system.