[abkolan]

As a non US/Canada based reader reading the article, I had a hard time grokking the article without visuals of how this was pulled off.

[Scoundreller]

Coin goes down slot like a vending machine hitting some sensor telling the machine that a $0.25 or $1 coin has been accepted. Dumb old machine has poor protections against reversing that process, especially with faceplate removed.