Interesting!

My wife is US born (although of Danish extraction) and I remember the first time we went back to Denmark with our (then) 21-year old daughter and her BFF... in no time at all, they had identified something they started calling "The Danish Glare," which is basically how Danes look at each other when they are not friends... just completely neutral. But to a pair of barely adult American girls... it came across as scowling.

I'm still seen as a bit "stiff" here, and I've lived here since 1981...