Every language has its quirks. French doesn't distinguish between ape and monkey (singe) -- the famous French novel "La Planète des singes" known from the various American movies in the original and remade "Planet of the Apes" series could just as well be translated as "Planet of the Monkeys". Similarly, German doesn't really distinguish between science and other academic subjects -- "Wissenschaft" can mean science, but also includes much of what people in English call the humanities.

I suspect there is a point you want to make. It is already a bit redundant to say that languages don't have perfect vocabulary coverage. In my post I was alluding to the formation of language corresponding to the formation of culture, and this specific case of English.

What does “economic”, in opposition to “social”, mean in this context?

Economic as in it doesn't cost money; social as in social/political freedom to do with it what you please.

Is it not free and gratis?

"gratis" is not a common english word either; you'd only use it to make this exact distinction.