It stems from popularity over here. "Electronica" is a very niche genre with a limited audience. While there is enough demand to sustain it, there is not enough demand for stores to bring in the titles in such quantities that they can get massive discounts. Not to mention that most of the titles that do make it over here are trance and house and mostly just the big name producers (Oakenfold, AvB, Tiesto, etc.)
I wouldn't have thought there would be this problem in Europe, but evidently I was wrong.
Thankfully eBay makes things a lot easier.