To some degree I agree. If you don't want to have anything to do with someone you have the right.
A few things to consider though. It's institutional for one. It's not just getting in a fight with someone and they stop taking to you. It's announced. To friends. Family. And strangers.
Shunning often has delved into people's privacy to get to that point, then exposed it to many others in what is a slanderous way.
Another thing is to consider is children. Most born ins are baptized before being considered an adult. They are making a choice of member ship into an organized religion/business before they can drink, drive, go to war, get married, etc. And now they are pushing for younger baptize and focused on kids. What happens when more minors are getting not only baptized but also reproved and even df'd? It could make for a sticky situation.
What I am getting at is personal reason to cut ties with someone happen often. A systematic approach from a group claiming charity etc could be a problem though. When they, a third party, are dictating your choices that if you don't uphold you could be threatened with the same punishment.
I do agree Simon but I think something will give somewhere. It's religious intolerance, and as isis and other maniacs make more headlines the Prarie of religious hatred and intolerance is going to get less and less popular and by extension jw shunning could get lumped in with that at some point. Laws made to protect Muslims or others could be used for jws in the future.
Also I gave often thought of this:
Would it mean the government would force people to talk to others they didn't want to?
And here is what I think would happen. Watchtower would have to change policy and preaching of the practice. I deep down believe they would continue it though. They have a way. For instance it doesn't say anywhere you can't have a beard. But grow one and watch the fireworks. They are good at enforcing unwritten rules that would just seem crazy in writing. But if the law forced them to at least remove the policy. I would call that a small win