Visible crew/equipment: In the very beginning of the movie, Ben is seen riding his bike over the bridge in an aerial shot. Near the top of the screen, if you look carefully at the end of the bridge you can see a police barricade at the end of the bridge. It is there because the bridge is closed for filming.
Visible crew/equipment: At the bar where the 21st birthday is being celebrated, you will see the microphone/boom come into the shot from the top of the screen. This happens while the "mom" is passing out the cut pieces of cake. It has a bright colored wind screen on it.
Answer: Casinos have always looked out for people counting cards, even before the real events that inspired this movie.
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