So I swiped again. I pressed 3 again. The same thing happened. I repeated this process three times. While this was happening, I was providing a running narrative, just in case she cared what was happening or that the credit card machine was broken. (She didn't.) Finally, I just said, "Well, it won't let me use the 3 button and it is sticking. I have another card I can use, though." So I pulled out my credit card, swiped it, put it back in my wallet, and looked at her. She finally looked up at me. "I'm going to need the last four numbers on your card, please," were the words she said. "You are an idiot and I can't believe you've been distracting me from my text messaging for the past five minutes," is what her face was telling me.
So I told her the last four digits of my card. Thankfully, I did not have to type them in. All I can do is hope that any future customers on Aisle 7 of Winn-Dixie do not have 3 in their PIN numbers.