@LysandersTreason
I don't know the other area of asian, but me as an asian to see that is quite normal.
It's just like as you said a "culture" but to be more precise it's called "etiquette", like you were addressing someone who is older than you with "Respect". Especially if those person is still "acquaintance" and not a friend /close friends.
I think it's quite wide known.
Because it will be weird when some stranger talks to you with
"Oh what's upp nigga?" "How you doing bitch" especially if they is younger than you.