Not to be rude, but I'm guessing that you have not been awaken in the middle of the night to Mortar Fire.
Yes I had thought of this since its no real secret. At the same time if I was searching the web and I searched, for instance Iraq, I could find a bunch of compounds without even having to be physically there, or knowing anyone there, or the area at all.
Common knowledge when your a local is one thing, being able to find something from across the globe is another!!!!!!!!!!!
I do, however, like the Idea of placing caches that will bear some longevity for the future, and not endanger anyone's loved ones.