@CuriousStranger this time it makes sense, the cats wouldn't need to know how and the elves aren't pescetarian, as they live in a savana away from any large bodies of water - it's probably the first time any of them ate fish.
For a real world example - Do you understand the concept of laying cod livers over boiling water to obtain a oil that prevents your bones turning to jelly? Unless you're from Scandinavia I doubt it.