As I type this at work, I am 20 feet from the "No Firearms Allowed" sign in our lobby. Luckily, I work armed as a guard. But this employer has decided no firearms are allowed in the building, and has chosen to ignore the parking lots. I know for a fact there are over 25 loaded firearms in worker's vehicles out there, another reason I stress to the outdoor guys to guard those cars well! Bad enough a car were to be stolen off our lots under our noses, worse yet with a gun inside! In this case it's more of a "Don't ask, don't tell" policy, the company knows there are some folks with guns, but as long as they stay outside, no one cares.
Were I to run a company that didn't have public access, I'd want all the armed employees I could get! If one were to go bananas, the rest would take him out, possibly before he ever got a shot off!
Papajohn