It was an actual beer can, but with a non-alcoholic liquid, so it was just a vessel. When caught, they discovered it was not really alcohol in there but it didn't matter and he was still fired immediately. I mean, if the vessel says 0% alcohol but Heineken (an alcohol brand) on it, I dunno what they would do.
Firing that guy may have been bullshit they got away with. I don't know if he sued or not. If he did I don't know if he won or lost. All I know is he was fired immediately. Someone also got written up for having a Maxim magazine, the same issue that was available at the store 100 feet away. Was it obscene? Or was it only obscene in a federal break room?
When vaping first started people were doing it all over the facility until they banned it. When that came down there was some official FAA language that said something like "smoking is not allowed on position, nor is vaping which is the appearance of smoking". It's not real smoke (akin 0% alcohol) but will still get you in trouble.
In any event, we won't know until someone breaks out a Heineken 0% on position. Trial and error. It was your idea, so give it a shot and report back.