Being a security guard cannot be that difficult. I see them in schools, at shops, and on the streets. Most are fat and the vast majority are old. Maybe it is cheaper for companies to hire a "disabled" or elderly person instead of cameras and a security company that comes in case of emergency. That coming is not fast, by the way, and you don't see any spry men or women there either who are strong, fast, and smart enough to arrest burglars or vandals.
As for the big shops they do know about theft and theft is factored into the selling price. Companies that hire the disabled, the elderly, or young people, for example, are doing something good for society and getting money for it. Of course, that sounds a lot more interesting than spending money on a company, expensive cameras, and all that technology behind it that also eats up power. A fat, bored guard like that will be happy with a sandwich and a cup of coffee and, of course, his own chair behind a high desk where he won't be noticed and can "work" on his phone undisturbed. I suspect it involves playing games or gambling like the security guard at a local supermarket used to do. If he was not working in the shop he would stand outside intently peering and tapping away on his phone while he fiercely pulled on his umpteenth cigarette. This guard saw and heard nothing I can assure you. He would not move a step if the premises behind him were looted or on fire. By the way, he was not fat but just not interested in his dead boring job and therefore far active. Could he have been fired? I haven't seen him standing next to the waste bin for some time.
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