An Interesting subject - I have travelled and lived for quite some time in South east Asia, Borneo, Bangladesh, Malaysia, Singapore, Thailand, Korea, Hong Kong and Japan. I have seen so many shades of shunning both at home in Australia and during my travels to believe that it is inherent in everyone. I have been guilty of it myself. Have you ever left some one out of your group intentionally?
I beleieve that inclusion gives you life and happiness, exclusion gives you power - for a short time. I prefer to include people and be happy.
Have a good life!