About three years ago in Wiesbaden, this trend started up in grocery stores....Sushi-shop. At the time, I was shaking my head. It was a small corner of the store, with two Japanese guys carving up and making plastic trays that you could buy for six to twelve Euro for take-out circumstances.....with a refrigeration area with oddball Japanese drinks, ice-tea, etc.
Well....about two miles down the road is my second-nearest grocery (small town of 15,000 residents)....and I noticed this afternoon as we entered....five guys were busy putting up their Sushi-shop within the grocery.
I asked my German wife about this whole thing (she's not a Sushi-person), and even she's admitting that this whole thing has been oversold. They are counting on sixty-odd people stopping off each morning and purchasing a Sushi-tray for lunch-time.
Just on the cost level.....it's a question mark, each one of these shops require two actual Japanese folks to operate.
Long term trend? I just can't see more than two-percent of German society having the willing nature to eat Sushi once or twice a week.