But that's the whole thing. Amazon.de isn't selling Brick Bank, but a 3rd party seller is selling it through Amazon Marketplace. Apparently that reseller doesn't want to sell it to you.
I know what you mean. I refuse to buy the Brick Bank for €170 in The Netherlands when it is sold in Germany for €150 ! I'll just have to plan a day trip to Oberhausen some day and buy it there, next to other sets that are much cheaper in Germany than they are in The Netherlands.