I'm not a lawyer, nor am I familiar with how my neighbour countries define public spaces. My response was based on the fact that for tobacco legislation, for instance, public spaces are defined as follows by the EU commission:
"places accessible to the general public or places for collective use, regardless of ownership or right of access"
- Directive 2014/40/EU
This implies restaurants. Another paper by the EU commssion regarding terrorist soft targets describes crowded spaces as public spaces as well.
Given all this, I assumed that some countries in the EU share this definition, and some don't. Because in the end it's up for each country to decide, and it's always a mess like that.
I don't know about "public place" in Germany, but that certainly isn't universal. In my jurisdiction (Canada), "public place" effectively means any location that is open/accessible to the general public.
Great. Can you provide any resources to back this up?
In this case, the person is outside and not on the property; if the restaurant wishes to be private they can take measures (curtains or blinds) but they’ve chosen not to.
This is where jurisdictions differ and is not cut-and-dry.