Same goes with India as well.
I have always wondered about this, may be it is the trade-off between getting caught and the sheer desperation to make money that tilts the moral compass to act in unethical ways.
A very western sentiment. We often deride the quest for profits, demonizing people who put profit ahead of something more noble like safety. But in places like China "profit" is life. China has seen starvation in living memory. In countries without social safety nets a failed business likely means utter destitution, very often leading to physical violence. The people who run restaurants, and certainly the people who work in them, are not chasing profits because they want to drive nice cars. They are chasing profits because they too want to keep eating.