Because it cost $600-700 to ship 2nd day air and there are custom charges too.
They dont get charged for customs as far as I know, and shipping a S2 from china doesnt cost nearly that much via UPS.
There are heavy customs charges for European customers.
You guys dont appreciate the 2nd day shipping service Bitmain provides, it cost almost the same to ship s1 as the actual cost to manufacture, so profit margins are slim.
For s2 I dont know the weight, say it is 14kg:
An example: ship to US.
$584 usd for 8am deliver, for end of day delivery is $494 usd. 2 day shipping.
Shipping USPS is cheaper but they dont have 2 day service, only 3-5 day and thats about $210.
Going to Europe and England is alot of customs duties.
PS. I had a small problem with one of my s1 before but since it still worked 100% I declined to ship it back for service because shipping would have cost a ton (even the slowest way), and I would have lost valuable time mining.