Again, I can't see any robbery being foiled by someone not being able to walk in through a fire exit. Besides, CCTV coverage in casinos is generally extensive and would quite clearly show who opened the door.
People seem to be grasping at straws to justify it. To me it seems quite simple. Secure the money properly. Money doesn't have to escape if there is a fire. If someone manages to get through all the security to get to the money, what difference is a fire exit being locked or unlocked going to make to them? (As opposed to persons wanting to escape from fire, what difference does a locked exit make to them?)
Basically, I feel that there are other ways to deal with this type of security without hindering escape.
There are circumstances where I would not have overrides on fire exits, but to protect money is not one of them.