My SO worked at one for years. He could not care less. Sometimes when it was obvious someone was returning a case of formula they had just stolen (like it was January and the case was not cold from being in a car outdoors) they would roll their eyes, but they'd still do it. What can you do?

There was this hilarious cashier once at a store I used to go to, who had some movement disorder that made her act like the Chicken Lady from Kids In The Hall. As a result she couldn't be bothered to memorize produce codes for scanning, and if she didn't know what something was, she would just toss it in your bag without ringing it up. I got a lot of free lychees that way.