Perhaps it would be helpful to examine some specific "traditions"?
I come back to values/principles as being important to pass on. Traditions are just arbitrary rituals. But people tend to attach emotional importance to them and then end up defending them even when they conflict with contemporary values. Perhaps the main sources of this emotion are related to notions of heritage and ownership. Perhaps this can be connected with evolution whereby one wants to protect the "environment" in which one was born and raised because, by definition, this was a good environment for our genes.
Around the world there is a conflict between an obsessive desire to maintain "purity" of tradition/ethnicity/language/religion and principles of equality and inclusiveness.