I think there is a difference between going "drinking" and say, having a drink. When I would come home from a day on the job of being a policeman, I might have a beer, maybe 2. Not a big deal. I don't go out partying or to an octoberfest with a gun, that's insane. Likewise, I don't carry if I go out to a restaurant and have drinks. I don't drive either. My wife doesn't drink, so she becomes the designated driver. If I think we need a gun, she carries it. I also want to mention...Some people just should not drink at all. Some people can't handle alcohol. It changes them for the worst. They are not safe doing anything after a few drinks...even having a conversation. It comes down to knowing one's limitations and abilities. Some people are perfectly fine having a beer with dinner and being armed. Some shouldn't be within a mile of any weapon, vehicle or machine after 1 drink.
I always refer to a quote from a senior Lieutenant when I was first on the job. He was addressing roll call the day after an officer got in some trouble involving drinking after work. He said, "If you can't drink...(Slow inhale of cigarette...slow exhale...)...DON"T"