Well this is news to me (in my neck of the woods) but I would have done absolutely nothing. Risking my life and innocent patrons for the contents of a cash register belonging to a multinational corporation?
Resisting strong arm robbery is SELF DEFENSE not defense of property!
It seems to me (and I've posted on this before) that a lot of people can't distinguish between simple theft (illegal removal of property) and robbery by force (coercion via threat to life).
With simple theft (aka burglary) the criminal takes something but never directly threatens you (or may never even have any contact with you at all). For example, you come back to your car to discover a window smashed and stuff stolen. You and the criminal never had any direct contact. In a similar fashion you may arrive just in time to see the criminal run off into the distance. Again, no direct threat/contact. This is theft.
However
Robbery by force involves the criminal directly approaching you and making some sort of threat. That threat is almost always a variation of the hoary old chestnut of "your money or your life". In that case a self-defense response is NOT you protecting "property", it is you protecting your life and well-being which the criminal just directly threatened in an attempt to make you submit.
Each individual must evaluate each situation and decide on the best course of action, but in scenario 2 if means, motive, and opportunity are all met then lethal force
may be an appropriate response.
Every time I hear the argument "just give them what they want and they'll go away" I'm astonished at the notion that I, or anyone else, should believe that about someone who was already far enough into criminal behavior to threaten violence and injury in order to rob me in the first place.
If they are far enough outside of the normal social boundaries to perform the bold, face-to-face action of robbery by force, then I tend to believe they'll do whatever else they please as well regardless of any "deal" they claim to be offering me.
Or more specific to this particular robbery. If someone comes into a place of business, makes some sort of demand, and "backs up" that demand with what a reasonable person would consider to be a legitimate threat (such as pointing a firearm) the entire event has ceased to be about property and is now about the threat to yourself and others.
Does this mean you should "just act"?
Hell NO! One should ALWAYS try to review the situation at least a little to determine what all of the options are. Additionally this is also one of those classic scenarios where you MUST remember that
the perp may not be alone.
Even if you are able to deal with the obvious threat it is critically important to remain alert and aware of your entire surroundings in case the bad guy has backup present (just outside, in a car, or even in another part of the restaurant/club/stop n shop, etc. That's why it's so important to avoid acting too fast. You must assess the ENTIRE situation as much as possible before taking action and you MUST assume that the criminal has partners.