If the parking was obstructing something else you can report it to enforcement for towing/ticketing or the owners of the lot. If it was not obstructing something else then you are being ridiculous and trying to put people in their place. I read this reply as nothing but ego and lots of assumptions (shooting my brains out, wtf?)

Leaving a note and running away is passive. I see what you mean, but disagree.

Its stupid and petty. By calling out an asshole this way you show yourself as also being an asshole. Resorting to passive aggressive name calling and insults from mild inconvenience is not a good look.