This is the first I am hearing of BW3s "Gun Free Zone". I really liked that place. I'll swing by my local one here in Missouri and see if they have a sign. Granted My feelings are not hurt that badly as I haven't visit a BW3s in ,,,,,, I can't remember but its been awhile.
I guess no skin off my back.
Regarding the sign doesn't carry the law, I've heard too many stories at the GS and at classes about how business's are not asking you to leave if they suspect you of carrying a firearm. They are simply calling the police and if the LE are having a bad day they will issue a citation/fine.