Those doors are controlled electrically. The cashier can open them by pushing a button from the inside.
7 seconds sound clip from the Ocean's 11 (1960) movie soundboard.
You can hear this line at 00:56:23 in the Blu-ray version of the movie.
Quote context
[...]
- Let me ask you: What happens if you knock out one of these towers?
- You get a short-circuit when the cable touches the ground.
- Rheimer and Josh are the demolition men.
- We need you to open the doors to the cashiers' cages, 'cause that's where the loot is.
- If the button's on the inside, I can't push it from the outside.
- But that's exactly where you're going to push it from. The outside.
- The auxiliary motor kicks in automatically. 20 seconds and they're back in business.
- Except they won't quite be back in business on account of you, Tony.
[...]