Just as a point of reference, I note that here in Utah (with our image of being very anti-alcohol), we have no laws limiting the otherwise lawful possession of firearms in restaurants that serve alcohol, nor even in bars. OC (with or without a permit) or concealed (with a permit). Your choice.
Neither do we have any law against consuming alcohol while legally armed.
The only law we have in this regard is that one may not be intoxicated while in possession of a firearm. "Intoxicated" is taken to be the same BAC as for DUI. Police officers are exempt and can be over the legal limit while still armed and not be in violation of the "intoxicated and armed" statute.
So if a mature adult wants to have a drink with a meal and then drive home all while legally armed, that is a personal decision, not a matter for criminal law.
I know many drinkers who will completely abstain from all alcohol if they are going to have drive themselves home or if they are carrying a gun. They figure, 'better to err on the side of caution." I certainly respect such conduct.
I know others who know their limits, stay well within them, but will have a drink to complement a nice meal even when they are legally armed and/or will be driving home. I have no personal beef with this approach either.
Near as I can tell, we have had about zero problems in Utah with private citizens. We had one case recently of an off duty, possibly intoxicated officer shooting someone at bar. He claimed lawful defense of a third party. BAC tests were taken so late as to be inconclusive as to his BAC at time of shooting. And the shooting was ruled officially justified.
There are the usual stabbings and occasional shootings outside bars after closing time. Most of these seem to involve those who are not legal to carry a gun anyway.
As in most areas involving law abiding citizens and guns, we just haven't seen a problem with our lack of excessive laws preventing the otherwise lawful possession of firearms in bars, nor banning any consumption at all while carrying.
To each State their own. But I just thought I'd pass along a data point for my friends in the Commonwealth of Virginia.
Charles