I work for a company who has such (idiotic) rules for employees, no firearms on premises or in vehicles, but has no such rules for anyone else coming on to the property. In the last 6 months, I have seen at least 10 customers carrying openly (kinda cool, I always make a point of talking guns with them) and who knows how many CCW.
Point is, what is the point of these rules? If customers can carry, why not just require that all employees wear shirts with targets printed on them? The store is not posted in any manner, so anyone who is not an employee is free to do as they wish(within state law, or disregarded, as you please).
Personally, I disregard the company rules. My well being is worth more than my job.