I work a store that sells baby items along with other things. Commonly our clothes are almost always on sale, so I nicely made a habit of checking sells on them from the register(it'd tell me if there was anything, ect.) One guest got an outfit with a Bogo so they could get one free. I nicely told her she could grab another and bring it back. She wouldn't even have to wait in line again. When she came back she threw the item at me, hitting me in face telling me how we 'should've had a sign up!'