Well noonehome, objectivity is hard for me on this topic but here goes....
Shunning is found in many societies and even among animals. Therefore shunning can serve a purpose. It can help an individual to moderate their behavior to remain part of a group when survival depends on being part of a group. It can help the group identify individuals that might be of danger to the group.
The thing is, you would only find that being used with the most extreme examples of anti group behavior. Murder for example (not killing - that is different than murder).
What the JW's have done is take the concept of not associating with someone spiritually and applied that to practical day to day living.
Completely lacking any factual basis anthropologically OR scripturally speaking.
If a JW doesn't want to spiritually converse with someone at the Hall, that's fine. But to take the "shunning" outside the Hall or anywhere near the family arrangement is an over reach on their part.
It smacks of the same pharisaical mind set that Jesus condemned. It isn't scriptural. It isn't applied with fairness.
It has become a cruel aberration that serves the purposes of a harsh leader - the governing body.