Physically assaulting people is obviously not right. However, the man who was punched really should work on his people skills. If I were stopped upon entering a shopping mall and asked to deposit my bag, I would be agitated, too. What kind of stupid business practice is it to forbid me from carrying my bag in a mall? I would also be more upset if the person refuses to get his manager upon request and then tries to stop me from walking along physically. That's absolutely inappropriate and plain rude.
In China, you don't have to look hard to find rude people, ruder than most people you meet in Canada. Of course, there are rude people everywhere, but there are in fact fewer in Canada. Also, in Canada, when you feel you are treated unfairly, you can always complain. Usually, your concerns do get resolved. There are systems in place to deal with complaints in Canada. Most of the time, these systems are not existent in China. People often get frustrated when they are offended and have no-where to go to express their frustration.
It's still wrong for the woman to hit that man, of course. The woman's behavior shows her ignorance, but perhaps, this incidence does reflect some of the issues exsisting in China and in Chinese culture.