Earlier quoted context omitted.
It would be quite a bit of work, to attend a very limited use case. Every Catalan (or Galician, Valencian, Basque) speaks Spanish, as do the vast majority of the expats I know (and I'm one myself). You can still access the specific site of the language you are interested in. Or, in the worst case, use Google translate.
The point being, location != language. I've been doing eCommerce for a long time now and the number of site that realize this is shockingly limited. With a few exceptions, the translations you are using for a country website's language are possible to use for any country where a visitor wants to use the language. Exceptions include things like country specific product features and such. Those kinds of things would ne…
But apart from the data and tech you need people implementing it, and I can understand most companies not seeing covering your/our case as worty of the added development/maintenance cost that it would entail.