There is an old joke. How do you tell an extroverted Estonian from an introverted Estonian? He stares at your shoes, not his own.
There are (at least now) plenty of “extroverted” Estonians, but I’ve heard dozens and dozens of stories of the “don’t make eye contact, just keep walking” variety during the USSR.
Also, staring at either party’s shoes may mean their own smartphone these days...
For the reference: https://images-cdn.9gag.com/photo/aj6MYgw_700b_v1.jpg
https://external-preview.redd.it/UMjBaFaE-dFYMu_VZ8nKO4_tj0E...
http://www.linkbcit.ca/wp-content/uploads/2016/02/Finland-bu...