Yeah there is some states where a person could not even keep a firearm in their vehicle on company property. Disarming the person not only at work, but on their way to and from work.
A large percentage of the population also stop and do their shopping, pick things up, pick up kids, or go to recreational activities when leaving work. It is when they get things done before returning home for the day.
This is especially true for those that commute a long distance, or live away from the stores and denser population centers.
So if they don't have a gun at least in the vehicle they won't have one to put on when they go do all their other normal activities after work.
(While storage in vehicles of handguns is not recommended anyways, that just makes them available for theft and the arming of criminals, so the person wearing the gun the whole day is better.)
So they are unarmed for most of their time spent in public as it will be doing things after work, unarmed at work, unarmed when they leave and arrive at home, and unarmed during whatever distance they walk to and from their vehicles. Essentially they become disarmed at all the times they have the greatest potential of needing a firearm.
Which in the end makes their Concealed Carry license go almost unused most of the time, at least 5 + days a week, and most of the time when they are out in public.
In the end making the effect that permit has on safety almost nothing, providing little to no benefits in life to that individual or anyone else they could come to the aid of.
So work restrictions can effect a lot more than just the hours at work.