c_yeager, you've got it wrong. Imagine you're an insurgent/guerilla/terrorist/whatever. You know that in past incidents, your comrades have found that a certain proportion of their weapons have been sabotaged, and some of them have come to sticky ends as a result. You now can't trust your arms caches, as you have no idea which one(s) have been found by your enemy and "treated". Are you going to risk using any of those 10 grenades? Sure, only 1 may be booby-trapped, but how do you know which one? Are you willing to take a chance?
Not me, if I were in that situation...