That makes sense. My main context for comparison is US vs PL, and there's a largish difference between strangers and in public or service people and a much smaller difference with friends and family. If you start talking to a stranger in the grocery store in the US because you were both reaching for the same milk you might get a very big smile. I would never expect such an exaggerated reaction in PL, just a small nod or pardon me.

Also, service people are not supposed to be fake smiling, we are actually expecting their emotional labor on top of the labor of their job. They are supposed to be cheering us up with their genuinely good attitude and "changing someone's day for the better" with their smile. It's all pretty exhausting.