Yes, all part of the mix. IIRC, in much of Asia, blowing your nose into a linen handkerchief in public and then neatly folding the handkerchief and returning it to your pocket is viewed with disgust - a major cultural faux pas. In fact, it's offensive to blow your nose, yawn, or even clear your throat except in private. I've seen 'em spit on the sidewalk without any hesitation, though (maybe that was a message aimed at me?)
Ever look at the sidewalk near were asians hang out?
Chewing gum everywhere!
Don’t sneeze in public but ok to spit your gum out all over the place.
interesting people....
Once, while living in rural Japan, I was running late and stood on the tiny train platform eating a banana for breakfast. That was taboo and for years I was remembered as ‘the gaijin who was seen eating a banana on the train platform’.
‘Hi my name is ******.’
‘ Oh, ******-san. The gaijin who was seen eating the banana on the train platform. Nice to meet you.’
When I worked in China in the mid 70s, I found there were no people in the world who spit as much as the Chinese. Public defecation was norm, too. Maybe those habits have been curtailed somewhat by now.