It is a remnant from the Northern Song Dynasty, as a form of etiquette and being polite, to not to disturb them while eating.
"凡往见人,入门必问主人食否 […] 度无所妨,乃命展剌。有妨则少俟。"
“Whoever you visit, you should ask them if they have eaten or not […] if they are about to eat, don’t enter the house until after they finish the meal. Otherwise, you would be intruding.”
From the book "Lü Convention" 《吕氏乡约》
For greeting, you could also say (in person): 吃饭了吗? / 吃了吗?
if you know them a bit better
So in short words, propaganda makers are lazy, want to work more efficiently, so they censor. Problem is China's image in the liberal west, they use this again as propaganda. endless circle...
@betterredthandead
@lemmygrad.ml