I would like to add two additional observations.

Density of population in a society with limited products and services rewards aggressive behavior when purchasing and using transportation. If you wait politely to get on a bus, you will never arrive home. Before the inclusion of the 'bakery-like' number system in Chinese banks, teller service was non unlike the floor of a commodity exchange, customers yelling and waving for recognition.

Family is the religion of China. The demarcation between treatment of family members and the 'other' is significant. My Chinese wife would routinely scold me: "You Westerners treat strangers better than your own family!"

As China's consumer economy develops and as the younger Chinese evolve non-traditional western-influence family relationships, I already observe these aggressive behaviors gradually 'normalizing'.