"No way to store fish" can't be right. Ways to store fish, also called preserving fish, have existed for eons (even the Wikipedia article for "Fish preservation" starts with the words: "Ancient methods...". It must have meant no way to store fresh fish. Even that wouldn't be strictly correct because you could use ice to allow a fish last considerably longer. Often it would just be too bothersome and enocomically unfeasible. In a fantasy world ice magic might help tremendously, though.
But then again, if it's a world without cats, it's possible the people are just too stupid to preserve fish.