If you stand at any train station in Japan around 20 pm you will notice people standing in circle, and you will think “Oh they are praying?”
No no, just friends saying goodbye. I personal found it very interesting and sometimes a bit annoying and I call it “The sayonara Circle”.
The personal area is a sensitive issue in Japan and at the time greeting is limited to bow their heads and say “mata ne!” or see ya! but in my personal opinion people want to express a bit more, especially when saying goodbye but the rules of social coexistence, forbid this manner and Japanese people limits their feelings to just see each other with a smile in their face.