Grab a Chinese guy and drop him somewhere in one of those silly English speaking countries that most of us come from and he'll have his own share of WTF?!? moments, some of which will be accompanied by the urge to smack some sense into the locals.
As one who works extensively with Chinese students, and the broader Chinese community in Australia, I don't agree with this. Chinese here tend to work hard, mind their own business and keep their opinions to themselves. Maybe they're too busy to gripe about trivialities which help establish and perpetuate stereotypes. Please note I am talking about people who have made huge lifestyle decisions, and very expensive ones too. Most have burned their bridges and are committed to a new life in a new country. Not many posters on expat forums are in that boat: sorry about the mix of metaphors.
Anyhow, that was not the main point of my previous post. People are not looking at what they are criticising or ridiculing in a full social context.
Perhaps the ones you work with are more accepting of what might seem like strange local customs because the are more committed, or perhaps they just know better than to complain too loudly about perceived local silliness in front of local people.
I'm sure there are a lot of things posted in this thread that the people posting wouldn't loudly proclaim on a busy Chinese street corner (especially with a translator handy to make sure that everyone understood every word).
As you pointed out previously, there are Chinese people who are less than pleased with the actions of some of their fellow countrymen. I've seen plenty of things done by westerners, both here and in the west that made me cringe too. Every country has its share of people who seem determined to give their nation a bad name.
Every country also has its share of accepted local customs that leave outsiders wondering just what the locals have been smoking. If everything seemed absolutely normal and made perfect sense no matter where you go, traveling would be a lot less popular.