"If I had a card for every store I shopped at, my wallet would be THIS BIG!"

It was a pretty slow night and this old guy came through my line. He bought $50 worth of cat food. When it was rung through and bagged, he asked for a pen, filled out his check and handed it to me.
"Do you have a Grocery Store card?" I asked.
"Nope," he said smugly, "It's so stupid when stores have cards. I don't believe in them."
I fought to keep my eyes from rolling and flashed my light on for assistance. Justin came over and I explained to him, "This man wants to write a check, but doesn't have a Grocery Store card." Typical ignorant shopper. I bet he also doesn't know the store closes at 9:00.
"Oh, that's okay," Justin said, "We can sign you up for a card right now--"
"I don't want a card!" The man cut in rudely. He looked at Justin and squinted his eyes sort of like he was sizing him up.
"Every store has these useless cards," he said to Justin and I, "Well, if I had a card for every store I shopped at my wallet would be THIS BIG!" As he said it, he spread his arms out dramatically.
I was trying to keep my smiling from turning into full blown laughter. Josh was grinning, but he literally always has a grin on his face even when he is delivering bad news.
"Yeah, I understand," Justin said and I nodded sympathetically as if we didn't think he was a crazy old man who should just shut up and get the card. "But you need to have a Market Basket card to pay with a check." The old man was outraged.
"Fine! Fine. Okay. Well, you can put all this back!" he said throwing his bag of cat food on the register, making a scene now. "And I want my check back!" He ripped it out of my hand. I lost some control and started to laugh. Justin and I exchanged looks and I could tell he was about to laugh.
The old man stuffed the check into his pocket mumbling angrily words like "Ridiculous" and "Stupid" and "Unbelievable".
The head of the Front End, Mark, was standing in front of the desk with his arms crossed, a smirk on his face. He had been watching the whole thing and I could tell he thought it was so funny. As the man walked by him muttering loudly and clearly, Mark called out with a huge smile, "Thanks for shopping!!" The man spluttered, "I DIDN'T!" and kept walking.
"Have a great night sir!" Mark called after him.
"I WON'T!"
Mark was laughing now. A few minutes later I saw Justin explaining what had happened to the assistant managers, spreading his arms out to imitate the old man.