Alan, your comment reminds me of an old saw:
"Figures don't lie, but liars can figure!"
There's nothing that can't be twisted, distorted, or misapplied by the incompetent and unscrupulous. Heck - look at the case loads in civil court!
At some point, folks have to engage their brains. Will honest folks sometimes disagree? Sure. Most times, compromise is easy, accommodation is cheap, and everyone has better things to do than to argue.
There are two ways to write a rule: as a general principle, and as a specific rule. If folks are going to be deliberate idiots, then general rules fail. As Paul Harvey says. self rule can't work without self control.
Naturally, specific rules are never specific enough, nor do they fit all situations.
Back on topic: Let's ask "how is a vending machine different from all other machines?" I submit that they are subject to unique forms of abuse .... with money as the trigger.
Sure, the electricity doesn't care if there's money within. Thieves do - as do those who have been cheated. It's just not sporting to zap those who are tipping, rocking, prying, hitting, and fiddling with the thing.
Likewise, the things are often placed where there is no supervision, and no access to the breakers.