First of all, you eat on the beach, which is amazing in itself. Second, the fish is fresh, well cooked and you can choose the one you want. Third, they have all sorts of typical products such as eggplant mash, prawns cooked in a earthenware with cheese (delicious), etc.
I see from comments below many people were ripped off; me and my girlfriend were not. Get smart, guys, here's what you have to do: go to the counter, choose your fish, get it weighed and they'll tell you the price before they cook it. Then choose the other dishes you want, they're all there in front of your eyes and you can ask the price of each of them. This way, you'll know how much you pay before you even start.