> how would a contained society actually work?
If a society is understanding enough to have CS, it safe to expect they would also not use CS for non-violent crimes.
So now what would CS for violent criminals with no skill look like ? Ok so this would be a prision/rehabilitation-center in traditional sense but with a twist that they can also leave provided the country have them.
If those countries are having them, that is. In medieval times banishment for the most part was equivalent to death (or turning to a life of crime as a bandit).
While a nice idea in theory, how would a contained society actually work? Prisons already are miniature societies (just generally not very humanely run ones). It'd still be a prison, albeit a larger one, wouldn't it? Worst case it'd be something like Manhattan in Escape from New York.
I'm not saying it couldn't work but it's not an easy thing to get right.