A Calculated, If Ridiculous, Response

I work in a diner, and I am finishing up with a customer who has been generally polite so far.

Me: “Would you like anything else?”

Customer: “No, all set.”

He places a $20 bill on the plate. The meal was $17.40, so I assume that the rest is a tip. He sees me place the money into my apron pocket and starts frowning when I stay still and watch him.

Customer: “No, you give me my change.”

Me: “Oh, sorry.”

He reaches out for my pocket and just about places his fingers inside, but I move away. I tell him that I will get the manager, as the customer simply picks up the menu again. I do not think anything of this, but when I start talking to the manager, I hear the sounds of plates smashing onto the floor.

My manager and I come out to see the customer casually walking toward the door, leaving a pile of food and plates from someone else’s table all over the floor.

Manager: “What’s going on here?”

Customer: “Those dishes that ended up on the floor should cost about $20, shouldn’t they? Consider this a lesson, you f****** thieves.”

I talk to the group that the customer had walked up to. It turns out that the customer had walked over to their table, holding the menu. He had looked between the menu and their food for a moment before reaching his arm out and throwing exactly $20 worth of food onto the floor.