My wife worked at Wally World for a few weeks one Christmas season. She was stocking shelves from midnight to 7 am.
She got to enter the security room one time and watch some videos.
Every foot of the store is recorded 24/7. And the tapes are reviewed. At least they were in Ontario Or 30 years ago.
They might not catch you the first time. But make a habit of stealing from the same store, and you will get busted.
I see the cop cars pulled up to our local Walmarts quite often. Whatever, they are doing there, they keep it very discrete. I have never seen action inside the store. But the cops are not hanging out at the deli buying lunch.