Nah. That is taken care of.
Just shot the "fake robbery" guys on sight and it will not catch on. People are getting shot for less by the police. And if you're taking that risk anyway, you may as well go all the way and grab some cash.
The problem is different: Green light or not, no camera will come down from the ceiling and stop or mitigate a robbery in process. There is a slight advantage of getting surveillance video out on the street slightly faster, but that needs to be faster than the criminal needs to be off the street. If you can't catch him right running out of the door and you need to go through witnesses, existing mugshots or face ID, you're still stuck with the usually crappy surveillance cam footage. Not much difference if you can track down a suspect after 5 hours or 5 days.
Or could it be that law enforcement puts more manpower into catching a suspect when it can be done with a wild car chase instead of desk work 2 weeks later? Any hold up that can't be solved within 12 hours is filed as cold case?
The only reason why this will seem work at the beginning is that robbers will see this as a choice between a regular and slightly easier target. If every business had that green light, robberies would be split up evenly between all stores again. It's the 101 of home security. You don't need it to make difficult to break into your house - just slightly more difficult than your neighbor. (Or you don't need to outrun the lion. Just the other guy)