In fact, the highest European salestax is something like 21% at the moment.

Europrices ARE a ripoff compared to the US.
I know people that mailorder stuff from the US and are cheaper off despite having to pay not only salestax and shipping but also import duties on the goods (tax and duties are very democratically leveraged over the shipping cost as well).
Stores are now starting to run their own import channels getting stuff from the US (which is somewhat illegal under EU law where any goods for which there is an importer or manufacturer inside the EU may not be purchased for resale outside the EU) to be able to compete somewhat with the online retailers.