It's pretty usual in my experience for the buyer to be expected to pay the fees at both ends for making the transfer. I used to have to go into the bank to arrange an international transfer and they would ask who would be paying the fees at the receiving end - I would elect to and they would check a little box on the form. Now I can do it from my desk, but it no longer asks the question, so when I paid Abel for the Heuer summit last year, it short changed him by deducting the fees at his end.
I guess the problem is more that it was a surprise for you that hefty fees were taken at that end, but I have been doing business with eBay Germany for more than a decade and the seller's approach is nothing out of the ordinary - there was a time when literally no-one there was accepting PayPal and transfers was the only way to go. A couple of friendly email exchanges auf Deutsch have netted me items that the listing was adamant would not be sent outside of Germany - I took paying bank fees on board as part of getting watches that I was unlikely to find in the UK but I guess the major difference is I was expecting them.
So, if it helps at all, this is par for the course from transacting on eBay Germany, you haven't been lumbered with a particularly difficult seller.