The cameras aren't on at all times. Employees are supposed to turn on the cameras to record abusive behavior by scumbags because the company found that people who were stealing were also abusive towards staff in 1 in 4 incidents. It's so employees have a record of the interaction. This also means when the thieving piece of shit makes fake complaints its even easier to ignore because the employee has proof.
If you're gonna steal food, go steal from walmart or some big retailer that can handle the losses. The little stores like this don't deserve the theft.