In my opinion, once you have gone above one language, there should be no technical reason for not providing any number of lingos on a website, unless the people who wrote these sites were a little bit stupid and actually hard coded the German, French, Italian into 3 copies of their code. (or a lot of IF and case statements embedded all over the place)

Normally you would allocate every bit of text a "number" and stick it into a language database table called by your application and reference this when you build up your "screen output" or other text based user info. (based on the language code/number being used at the time)

To add another language would probably just entail paying one competent bi-lingual person to add a new column of the new language into this one table and should not take more than a day or two and maybe cost the Coop 1 or 2,000CHF before it could be live and delivering yummy food to new EF'ers.

Anyway, this is what I did on the the few web sites and applications my friends and I designed and deveolped over the years. Standard practice, as well as common sense.

There must be a strategic, corporate or cultural reason why the COOP did not include English I reckon.