Cliques are inherent in groups, and groups are inherent, period. People want to cling together; this force is at work when you create a family, or for that matter, train with people at a dojo.

It is true that this bonding force is most often a function of fear and insecurity, and that sometimes a strong odor of fear and insecurity can make a particular group offensive. But why not have a heart and let it go? They're not doing anything you can't understand and haven't done yourself.