When I was younger and would go hiking or climbing in Scotland and Wales, I would definitely have to be quite mindful of "showing I was not a threat" when entering small village stores and pubs there.

The more densely and contiguously populated and area is, the easier it is to (a) feel a part of the "in group" (b) not feel aware of the difference between "insiders" and "outsiders".

My experience is that the behavior you describe in Americans is roughly proportional to population density and tourism levels. Areas with lots of people and/or lots of visitors do not require this "low threat establishment". Areas with less people and/or less visitors often do so. I think this is true of Europe just as much as the USA, and I would guess it is probably the same worldwide.