Of course not. They know that such a sign won't stop such people. They are trying to stop the idiot gun owns who have a need to fiddle with their guns while out and about. You know the ones, right? We discuss them here from time to time. They are the ones with guns that go off while standing in line, while in a seat in a movie theater, while standing at the checkout at Walmart in AZ, or that shoot a toilet in an eatery in Utah.
If they thought such signs would stop bad guys, then they would just put up a no robbery sign or no bad guy, but they don't do that.
This next guy hurt himself, a toilet, and a woman.
This guy managed to hurt a total of 4 people...
So folks think that by not allowing guns, the chances of something going wrong are reduced. Never mind they they occur at an extraordinarily small fraction amount of the time, even compared to bad guys robbing the place.
And this one, in a local Starbucks:
I'm probably twice as likely to be shot by an idiot than by a bad guy.
I don't understand the issue with the signs either, it's private property and if they don't want guns on it then that's their business. I have the choice of either leaving my gun outside or going elsewhere.
This has been discussed here before, and I still believe that your property rights trump my 2A rights every time.
P.S. - This one too, from today:
And this, also today:
If you take your gun to a gun show to sell, and you're too stupid to clear it before you go in, then maybe you don't need to own guns after all. In fact that's the one gun control measure I could really get behind: an IQ test.