Substitute "most European countries" with "most Bundes of Bundesrepublik Deutschland" and you will be closer to the truth. Otherwise, I'd rather doubt it. To say it bluntly, Europe != Germany

Nope, because that is indeed what happens at least in plenty of Portuguese, Spanish, Italian, French and Greek bakeries that I have bumped into across my European travels.

One thing is right though, many Germans think they are unique on this.

I'm from Spain. Yes you can find bakeries that sell sandwiches, especially in areas for tourists, but I would argue this is not the norm generally speaking. Bakeries for locals rarely sell sandwiches.

Searching for panadaria, bocadillos across random places on Google Maps gives me plenty results.

To me it appears those are somehow related to what I mentioned on my comment, "Those that only sell bread and nothing else, are very few and slowly going away."

On the other side of the border, most of those bakeries survive in small villages with an aging population, and have been wipedout by pasteleria/panaderia businesses in towns and cities.

Then again, I never been in tourist free areas when in Spain.