iTunes Store / App Store - change language

I have tried so many times to change the language in the App Store iTunes Store to English, and i am loosing patience because it's all in german, a language i do not understand.

That is because my credit card to pay my Mac things is from Zurich.

What I don't understand is, Switzerland has officially 3 languages: French and Italian, as well as German.

Why can't I switch to one of these languages, or english?