I was busted for shoplifting as a teenager and I sort of know how this works. The general employees (cashiers, service staff, etc.) don't give a fuck if you steal and will actually get in trouble if they try and apprehend you. Almost all large companies operate this way for liability reasons. They aren't insured enough to cover all of their staff in the event that one of them gets injured or killed trying to stop someone from stealing something. Much less costly to simply budget in a line item expense for incidental theft that's bound to happen.

Instead of the employees focusing on shoplifters, they have a loss prevention agent in the back watching cameras. Those cameras all over the place in all the big box retail stores, and they don't even look like those super obvious dome cameras anymore. Most people who steal and get away with it will eventually come back to the same store to do it again. They take note of your face/features and watch for you to return (also, the large chain stores will share this information with other nearby stores). As soon as you step through the door the next time you come in, cameras are recording your every move. That's exactly what happened with me and my delinquent friends. We ripped off the same store about 2-3 times and the last time was when the guy actually made his move and apprehended us. He waited for us to actually take something without paying for it and physically stopped us at the door as we were stepping through the threshold. At that point, they confiscate whatever you stole, show you the security footage of you taking the product and walking out with it, call the cops, press charges for petty theft if under $1000, and call your parent/guardian if you are a minor.

In my case, I got extremely lucky because the cops simply never showed up after hours of waiting for them, and eventually, they couldn't legally detain us any longer, so they released us to our parents without charges. My Mom was pissed and set me straight when we got home, and I stopped hanging around the dumbass kids who coerced me into doing it in the first place. We were also banned for life from the store, but I've actually been back to that same store several times as an actual customer and they didn't recognize me anymore. Or they just didn't give a shit.

If you just steal once, especially if it's a spur of the moment thing, a very low value item, or a complete accident, it's really unlikely that loss prevention will care. If they start noticing lots of inventory going missing, they will watch those sections much closer for suspicious activity. There's always the chance that you could just be randomly singled out by the cameras.

I've heard of some places not bothering to stop food thieves because a person who steals food from a grocery store probably desperately needs it, but I imagine they all have a line that they aren't willing to let people cross.

They have your face and whatever else information you give them when you check out. It's all covered in cameras. Doesn't take much. I'm sure they don't get everything and they have false positives. But if you become such a problem for them yeah.

I don't have any real experience with this but I think it's actually hard to catch the accidental thefts and such who they are losing so much money and starting to rethink these things.

Can confirm. Used to work for a big retailer and one day caught someone stealing (not food) and confronted them. I was a pretty solid employee who had been there for years but my manager had to fight hard to stop me from being fired; it was a really close call.