To address your earlier point that woz wasn't harming anybody, insinuating to casino security that you're passing counterfeit money is essentially saying "I am doing you harm." We generally frown upon people saying that, even when there's no real harm to accompany the statement.
Considering that the casino security person admitted the 2 dollar bills were legit currency, the fact that he intruded on someone doing nothing wrong and proceeded to basically interrogate him, it would be more accurate to say that the casino security person was the one essentially saying he intends to do harm.
Hopefully in the future he decided to not waste other people's time on his idle curiosity.
