Have you been chickened lately?

My wife and I were driving through the city recently where a traffic inspector was writing out a ticket for someone who must have been parked illegally.

My wife said in passing "Looks like another person has been chickened". I said "What?". She said you know "Booked, book book book, booked, book book book" and continued until I got it.

I didn't know whether to laugh or cry because I was just so proud of her terribly bad joke.