My guess is that Walmart is more concerned about finding a cheap way to deal with its parking-lot crime problem, for which it has taken a lot of flak, than it

My guess is that Walmart is more concerned about finding a cheap way to deal with its parking-lot crime problem, for which it has taken a lot of flak, than it is with national security. Finding a way to encourage vigilance on the part of customers while deflecting attention from the real threat (robbery, assault) seems as clever as it is cynical.