Sticking with the premise TAB, how "gun" friendly is your insurance co. , bank, car dealer, suppliers, vendors, etc,.. (I know you live in Ca, so that should be just about everyone you write a check to each month),...
Point being, this business man had some of his accounts and policies terminated. That "message" and attempt to threaten to put him out of business, or make his life hell, goes against the grain of a promotion (in a crappy economy BTW), to increase his business.
It goes against capitalism and entrepreneurship. OBTW, what he did was LEGAL. If his ins. co. "X" or bank "Y" dropped him for this promo. he should go elsewhere, and let like minded folks know why.
As far as liability, I'm sure you have a carjacking, gun totin, I've been robbed, gangbanging, steal your shi* clause in your policy, so your covered.