A good number of religions and cultural groups practice Shunning, some of the Jewish groups, Islamic groups, and some groups that are not particularly thought of as religious, like the Roma. If you go against their Rules in any of these groups, you either stay and take their discipline, or leave and be totally Shunned.
It is my hope that attitudes will be changed in groups that practice this evil thing, by it generally being recognized for what it is, a denial of Basic Human Rights.