I didn't think it was confusing. IMHO, if you were out and about and ran into a Buddy that said, "Hey let's get a beer." I would have no problem unloading my gun, locking the gun in the trunk, and the ammo in the glove box.
At this point, I am no longer carrying, concealed or otherwise.
Now I would drive to where I plan on leaving my car for the night, and park it. I would not enter the car again to get cigarettes or what have you, or decide I could drive home since I only had one beer after all, as I believe being in control of a firearm while under the influence will get you busted in most states, but that has nothing to do with concealed carry.
But, as stated above you need to check on local/state law about leaving the gun in the car. This has nothing to do with if you're in a bar drinking, or 50 miles away in church, this has to do with how your local/state laws require a gun to be transported/stored in your vehicle... do you need a lockable box? can you lock the ammo in the glove box?