It's not "my" rule. I never asked for it.

Found the actual law: https://www.ncleg.net/EnactedLegislation/Statutes/HTML/BySection/Chapter_20/GS_20-138.7.html

It looks like what I heard before was just incorrect, the law explicitly allows sealed containers in the passenger compartment. Also, the commercial vehicle exception is to allow open containers.

Funny enough, if you ask Bing a rather pointed question about whether or not a SEALED container is illegal in the passenger compartment in North Carolina, it says that it is... misinterpreting the available sources like what appears to be many other parties before it.

Regardless, I do think it's wise advice to put it in the trunk whenever practical like any object that could become a projectile in an accident.

I was specifically thinking of North Carolina when I made my post, but looking around the internet the no closed alcohol containers in the passenger compartment rule may only apply to commercial vehicles. It's unclear to me now since I can't easily find the law itself. Everything I saw while skimming seems to be secondhand info, and some of my search results say that it is specifically legal rather than illegal in a commercial vehicle, contradicting the others.

Apparently we need a lawyer to be certain. The only thing I can be sure of now is that I was told to keep it in the trunk even if closed so that a cop couldn't use it as an excuse. I thought it was a misdemeanor.

In some states it is illegal to have liquor in a compartment accessible to the driver while in motion, so the drive thru format would have to involve loading the trunk instead of handing the purchase through a rolled down window. That practically limits the order fulfillment method to curbside pickup.

Edit: Seems I had bad info on the state I had in mind but the myth came from somewhere. Anyone know what state might have a law about location of SEALED containers in a motor vehicle?