The problem with the 4 rules and the potential 5th is that the people who would obey them don't really need to be told and the people who need to be told won't listen no matter how often you reiterate them.
I read an article from Greg Ellefritz the other day in which he discussed what should be Vs. what is. The example he used was "By God I shouldn't have to lock my car in my driveways (or do anymore to secure my weapon than lock the car doors) because it's on my property and you're not supposed to there."
His point was that those people are absolutely right they SHOULDN'T have to do that but the reality is they DO.
That's the point I try to make when ever this particular argument comes up. Yes, the thief is 100% responsible for his theft BUT I'm the one who is out 600 bucks.