When you gonna visit Berlin the capital of German the thing you should see is KDW a huge shopping centre called by full name of Kaufhaus des Westens.
If you like seafood skip the shop and go for 6th floor. You will be able to buy there things to get to your home or eat right away in restaurants and shops. So yes you can gather a fish and decide to take it home raw or make them cook it for you.
Here is some stuff i got and seen there.
Shrimp sandwich
Fresh crabs, lobsters and fish
And i ate some!