Have you or have you seen someone open an item in a grocery store to consume it prior to checking out?

Have you ever opened a bottle of soda or a bag of chips while shopping for groceries and then have the cashier ring it out whether it’s empty or not? Why did you? Were you just so hungry or thirsty that you couldn’t wait until after buying it? What was the item? Did the cashier say anything about it? Did anyone else say something or look at you strangely?

Have you witnessed someone else do it? What did you think?

What are your thoughts about this? Do you think it’s right or wrong? If you haven’t, would you ever?