I think it depends on who is doing the shunning. I know of brothers who will still smile or acknowledge ex-members, but not go into a full length hello and hows life without your brothers style chat. Which I think is fair enough to be honest. But to completely turn your face away, literally. and look down your nose is childish and lacks dignity.
I have a theory as well, that if you are born into the truth and the society, then you are more likely to jump in front of a passing car than greet an ex-member. Due to a lack of fellow feeling for somebody who may be depressed and certainly in need of friendship.
Whereas, if you have delved into the excrement of secular society (at least thats how I see the world most of the time) and come out the other side, after experiences that enable empathy, then you are more likely to display a charitable attitude to whoever it may be passing your way.
The GOOD SAMARITAN is a fine example of extending yourself beyond your belief system... surely? Maybe the snobs within the JW society should have a closer look at that scripture.
Hmmmm .......