I used to work for a fairly large hardware store in the US. We had just opened the store around 9am, and I was the only one at the registers up front.
Enter Shady Tweaker Guy. He comes in, doesn't respond to my greeting or make eye contact, and goes straight for the "misc" aisle (where most of the theft occurs).
A couple minutes go by, and he reappears heading right for the exit with a fast paced walk. He's holding one hand over his jacket pocket, very obviously trying to conceal something he's taken.
He gets to the door, takes his hand off of his pocket to push it open, and bam, one of our big ass hunting knives falls out and onto the floor, making a bunch of noise.
Dude immediately froze in place, looked at me (looking at him from only a few feet away), looks down at the knife, looks back at me, and ever so casually strolls out, leaving the knife.
This whole stare-down happened in about 5 seconds, but it felt so much longer. It was such a strange combination of awkwardness, hilarity and a bit of fear.
I'll never forget you STG, keep workin on those thievery skills.