One possible answer may be that China with its strong Confucianist background differentiates between people in the "inner circle" and those outside such a (social) circle. That attitude includes strangers of Chinese origin and foreigners - Western as well as those of non-Han ethnic background (ethnic minorities in China). The last Imperial dynasty in China was the Qing or Manchu dynasty. They came into power by force and were never really accepted by the Han Chinese. The same for the foreigners from the West who made the Han Chinese feel humiliated from the time of the Opium Wars on till 1949 when the communists took over. They now look back to history and feel now confirmed in their ethnocentric approach.

There are other possible answers; it would make a post too lengthy to read to name and discuss all of them.

This thread was right on about the Chinese people's inability to recognize foreigners as equal human beings and about how tough it may be for FTs working and living in the nation.