Well, there are not that many tax-free places. If they didn't have quotas, there would no doubt be thriving businesses buying alcohol in Svalbard and selling it in the rest of Norway.
Meanwhile, the Swedes go to Denmark for cheap alcohol, the Danes go to Germany, the Germans to Poland and the Poles to Ukraine. Thus Ukraine is the fixed point of the alcohol-flow function. This theorem was proven when I was a PhD student in a research group which contained a Norwegian, a Swede, a German, a Pole and a Ukrainian - we extrapolated the Danish connection point.