When Richard Laermer walked into an eyeglass store in Paris, he was surprised to find fewer than 10 frames for sale, each displayed on top of its own large pedestal. He looked for another room or some sign of a second floor. But that was it.

A clerk stopped dusting. “Hmmm?” he asked.

Mr. Laermer says he couldn’t resist his reply: “Don’t mind me,” he told the clerk. “I’m sure I’ll find something in the 30 seconds it will take to look over your inventory.”

Mr. Laermer was shown the door.

Does sarcasm have a place in polite conversation?