Passes It No Sweat

(A customer brings over a pair of wool socks and a large pack of toe warmers to my till. He is in his early twenties, but seems nice enough.)

Me: “Getting ready for the cold weather? I heard it’s supposed to snow.”

Customer: “No, it’s for a drug test.”

(Thinking I didn’t hear right.)

Me: “What?”

Customer: “They help me pass my drug test, every time.”

Me: “…”