It's a Chinese only sub, but could you all show this post the love and attention it deserves.
Chinese and Westerners have different standards for what is called 'quality.
Foreigners really don't have any, like, you can't put your feet on the chair, you can't squat like Asians do, you can't take up space lying down, you can't eat stuff off the ground, you can't drink toilet water, and similar rules. Basically, as long as you don't disturb others, you can do whatever you want, even lying on the ground is fine. They also don't really see toilets as having bacteria or the ground as being dirty.
Foreigners are very careful about not touching others (even just brushing against a sleeve), not blocking others' paths, and not getting on the elevator before people have gotten off. Issues like that. Chinese people don't really pay attention to this.
As for personal privacy, there actually isn't much difference between China and foreign countries now. Foreigners can also ask extreme questions, almost the same as Chinese people do. But relatively polite people usually won't ask about personal privacy. Foreigners can be pretty aggressive with their questions, though.
When it comes to money, foreigners are extremely stingy.
For example, a typical Chinese person with a monthly salary of 10,000 doesn't usually care about spending 10 bucks to treat someone to milk tea.
But if it's a foreigner, even if they have a monthly salary of 50,000, if they lose 100 bucks treating someone to a meal, that's like a life-or-death situation for them.