Besides fearing that someone will go haywire and shoot the boss for continued unfair treatment, they (employers) probably are afraid that they might get sued if an employee successfully defends himself on company property. Proving once again that you don't have to be smart to be in charge.
We live in a VERY free state (some ways not so free.i.e not able to forcibly contest illegal entry by police) when it comes to guns. We just had a BUNCH of new pro gun laws go active 1 July this year. No need to have permit to have handgun. With valid IN CCW you can carry ANYWHERE in the state except a building housing a court room. Plus a few others that are eluding me. For the most part we are well represented in the state house at the moment...but that is NO reason to go lax. We must remain EVER vigilant as we can lose as much or more ground than we've gained in one erection cycle.