Personally, my sense is that "travel" through war zones is somewhat less rational than avoiding them altogether, escort or no, so I think that's one "benefit" I'm willing to forego.
The free-rider isn't allowed into bomb shelters when there's shelling, and he isn't allowed in evacuation vehicles if the battle is going badly.
Which is likely to be a problem if I don't substitute the one-time cost of my own personal shelter for the ongoing cost of someone else's shelter. Or if I don't own my own "evacuation vehicle" (read: car), since, once again, the defense forces can hardly leave my vehicle selectively undefended while protecting all the paying customers in the same traffic jam on the same road.
And, of course, the rather more elementary problem with that scenario is that, if you and I and our neighborhood come under serious shelling or aerial attack or some such, then all our houses are likely destroyed anyway, which leads one to ask what exactly you were paying for in the first place. A ticket to the private shelter?
Your call. During the war between the states, there was extensive travel between the North and South, for all sorts of reasons. A member of my church, who was a conscientious objector, regularly made the trip for pastoral reasons. He was often escorted by Union soldiers to the front, and was then escorted by Confederate soldiers on his way south.
But "safe travel" doesn't necessarily mean you're traveling near enemy lines. For that matter, enemy lines keep moving. The smart subscriber bounces his travel plans off the agency before making any sort of long trip.
And, of course, the rather more elementary problem with that scenario is that, if you and I and our neighborhood come under serious shelling or aerial attack or some such, then all our houses are likely destroyed anyway, which leads one to ask what exactly you were paying for in the first place. A ticket to the private shelter?
What are you paying for now? The possibility exists, however remote, that the Eastern Seaboard may someday be occupied by Hottentots. Many refugees would then flee west. Some will have vehicles, escorts and good maps. Some will make it on pure luck. Some won't make it.
As I said, you are correct that the free-rider problem exists, and it can't be solved perfectly. But, as I also said, it's nowhere near as difficult as the public-choicers like to pretend. "Security" means much more than "someone over in Iraq is dying for you," though that's part of it. It also means civil defense against terrorist emergencies, against invasion, against natural disasters, etc., and it includes many more services than simply sending infantry to fight and die.
Event he US military, inefficient as it is, does far more stuff than you'd imagine. They ship a lot of supplies to a lot of places. And with those great-big nuclear wessels of theirs, they can supply a surprising amount of distilled water in emergency areas. Private defenses, similarly, would involve much more than a bunch of guys with rifles.