I doubt it. Unarmed assault is one thing, but if you try to commit an armed crime in Arizona, it is open season on you. Literally you can get killed by anyone. Maybe a clerk, maybe a customer, an off duty cop, some grandmother.
If the owner is an SF veteran, he probably owns an arsenal and is a very keen shot. Probably not a good idea to try and rob him for at least the next month.
I'm thinking along the lines of LA gangs...Crips,Bloods,Latin Kings,MS 13.I'd be surprised if all these gangs haven't made it to Arizona.If my hunch is correct I'd bet that they wouldn't be afraid of a single guy...Special Forces or not.