It looks worse than it is, because:

1. US prices don't include sales tax.

2. All prices are shown in USD, which has fallen ~12% in the last few months.

Adjust for both of these and Western Europe gets the plans for 20% cheaper.

The sales tax is a fair point, but not the currency one. American companies are extremely quick to increase the Euro-denominated prices when this currency becomes weaker; six months would have been more than enough to perform the opposite adjustment. Anyway I can see how selling in the Europe has more friction (legal risks, costs of translations etc.), which must somehow be compensated.