Would you like to explain to the dealership that gave me a shitty old loaner Tesla why you decided to vandalize their property and make me have to deal with it through my insurance?

I think the reason most people vandalize secretly is so that they wont have to explain themselves at all. Generally speaking, they hope the vandalism speaks for them and don't particularly give a fuck if it dings some jerk's insurance. As for the golden rule, I think you've got that confused too: Most people who vandalize in this way are hoping to inspire others to do the same, so golden rule very much in play.