In Europe there are huge discrepancies in purchasing power between countries even inside the Euro zone but, at least when buying online directly from Blizzard, the price is the same wether you live in Greece/Portugal or France/Germany.

Having the same price for every country inside the UE and not using the actual conversion rate hurts even more the people in countries where average wage is bellow US wages.

It wouldn't hurt them that much having different prices for different countries inside the UE, just make it so you need a credit card from the country to pay the price corresponding to that country.

(at least there is amazon.co.uk and I am a little happier)