You had no intent to do anything other than pay for everything in your cart but later you realized they didn't ring you up for something.

Consider

- Your time has value too.

- You didn't ask to be put in this situation.

- Most likely, you've already given this business hundreds if not thousands of your dollars already (local grocery store, etc)

- Most likely, you've been on the flip side more than once where you are overcharged or double charged for something and the store certainly doesn't initiate jack shit to fix that type of error.

- Can you really say there isn't a difference between this and a shoplifter?