I’ve never been to Geneva. Should I be surprised on seeing a stop sign in English, or an advert for Canada Dry in a shop window?
No. You just might see some Golden Arches there, too. North American iconography is everywhere now, you see, just like American films. Don’t approach any of the natives, though, as they might be speaking German, Italian or French, which could be somewhat confusing for a person such as you.
Adverts for British and North American products will be in English, naturally. (Although it surprises me Canada Dry has an international market). But why traffic signs in English? That’s not the norm for the rest of Europe.
The STOP sign (in English) is in use throughout the European Union.