Logical... Controlled access to the lot should be required if they want to prohibit firearms on the premises in a motor vehicle.
I have noted many large commercial enterprises with expansive parking facilities have security that is virtually nonexistent. This conflicts with the right to defend yourself.
A covenant not to defend myself from force, by force, is always void. - Thomas Hobbes.The right men have by nature to protect themselves, when none else can protect them, can by no covenant be relinquished. - Thomas Hobbes.
It is sort of like the U.N. trying to force the Israelis not to defend themselves against the Phillistines when the U.N. won't do a damn thing to clamp down on them either...
Nothing wrong with an honor system. So your boss trusts you--hey, he doesn't know you like I do. :-)
A covenant not to defend myself from force, by force, is always void. - Thomas Hobbes.
Hobbes was an idiot, but this statement is almost true. Not completely true, but almost. Regardless, it has nothing to do with this case: the parking lot owner forbids the parking of cars containing weapons. This is not the same as requiring you to submit to a mugging, although you may find it inconvenient to defend yourself without a gun.
If the risk of a mugging is so very high, I would (1) negotiate with my boss to allow guns, or maybe (2) park somewhere else, or maybe (3) hire a security escort service, or maybe (4) convince the boss to hire security guards, or maybe (5) carry a gun but store it off the premises, for example in a rented locker next door to the workplace, or maybe (6) carry a switchblade or ballistic knife, or maybe (7) study Tai-Chi as a martial art, or maybe (8) carry pepper spray, or maybe (9) change jobs to a safer neighborhood, or maybe...
If you honestly bought Hobbes's reasoning, and you really believed that it was applicable, you would insist on carrying a gun inside the office as well.