Speaking only for myself, if I answered this call no one would get arrested. I would tell the CHL holder that at the legal request of the owner/manager he can't come there anymore and that would be it. If the complainant pushed it the most they could do is ask for a Criminal Trespass warning to be given to the CHL holder. All that means is that if they come back again after being warned they are subject to arrest.30.05 is a way cities have of trying to skirt 30.06. You can guarantee if you are caught carrying that you will be reported to the police and they might arrest you. I think they are counting on the cost of a defense against an unlawful arrest being too much to bear.
Take your business elsewhere and then call the people who own the business and tell them why you're now going to their competition. They probably could care less but you never know. Perhaps the manager of the establishment had the sign posted and the owner had no clue as to how it might effect his revenue.
These type of blanket "no gun" signs apply to LEOs too. If we're off duty and someone has one of them posted then we're supposed to obey their wishes. There are other places we can't carry unless we are on-duty and in uniform. A plain clothes officer on-duty cannot carry into certain areas and even uniformed officers can't carry into certain areas. Most of them are federally regulated but we still have to be aware of them.
In my humble opinion this 51% rule is nonsense. CHL holders should be allowed to carry there. If they do something stupid while they are there (or anywhere for that matter) then they should be held accountable (the same applies for a LEO).