Seems like money, really, is the root of all evil. We should always be on guard on every circumstances that we may encounter. And I hope that those people will soon realize that their actions are unjust. Hope they still have even the slightest conscience.
A lot of these robberies are actually committed by boneheads who are trying to steal cash during a face-to-face transaction. Hence, their stupidity will reach unbelievable depths in some cases. So, one lesson to learn from this is to avoid doing major transactions in places where you can be vulnerable - and yes, a weapon can be handy.