One interesting point about the purge is actually after a few years whether it would be that violent at all, sinse odds are most people would have the same idea as regards steel reinforced bunkers etc, so likely it'd devolve into a situation where anyone wanting to commit violence wandered around the streets and most people just sicured themselves at home.
funnily enough I imagine the major problem after a while wouldn't be the killing and robbings and what not, so much as the people who used the opportunity to commit either smaller domestic type crime, or large scale embezlement or the like, sinse it would be a perfect time for say a company to fire all their disabled employees or commit similar discrimination without needing to work around the law and find an excuse.
Of course, the purge is also predicated on the idea that the force which stops most people commiting crimes is actually the law, which doesn't seem to be the case for many people, , indeed when my brother worked as a criminal soliciter he said that the majority of criminals he encountered were more guilty of stupidity than anything else.
HeckI've engaged in several mildly illegal activities myself such as my brief experiences with canabis and occasional copying of things the fat cats wouldn't agree about.
I therefore suspect the purge would only affect a certain percentage of the population, and likely the rest of the population would take measures to control that percentage , sinse after all where did laws come from in the first place?
This is why I suspect the major problem wouldn't be the thugs wandering around the streets, so much as all those corporate and middle management morons who currently have to work around the law to enforce their petty little whims on others, and for many of whom the law is indeed the only restraint on their greed or prejudice, and often not much of that sinse there are ways around it anyway.
With our dreaming and singing, Ceaseless and sorrowless we! The glory about us clinging Of the glorious futures we see,
Our souls with high music ringing; O men! It must ever be
That we dwell in our dreaming and singing, A little apart from ye. (Arthur O'Shaughnessy 1873.)