It is very strange, especially since it's available for download, so there's no shipping costs involved. I can think of two things why it's not available:
1) They don't want to be bothered setting up the site to convert euros to dollars, and there's not a big enough market in Europe for the incentive.
2) The software probably comes with support, at least for the first 30 days. The cost for international phone charges may be prohibitive.
But I'm just guessing...
Think of food as fuel for the body instead of feeding emotions