I hate door dings - we probably all do. Sure they can be fixed but it's a pain in the ass to deal with. My problem is what it says about other people. There are so many drivers who have so little regard for other's property that they don't think twice about slamming their door open into the car next to them after parking. Of course, leaving a note is so last-century, and it would imply a conscience, which would imply personal accountability - something everyone seems to be lacking these days.
On the occasion when I find a door ding and it obviously matches the car next to me (position of ding, colour of paint, my door paint obvious on their door etc), I'm left with a dilemma. Do I "do unto others" and scratch the hell out of their car, which lowers me to their level? Or do I be the bigger person and just leave? The morally correct answer is to drive away. But I'll admit on more than one occasion, I've done damage to the other vehicle purely out of revenge.
For most people, you wouldn't go up to someone in the street and punch them, or take their wallet, or break into their house. So why is damaging their vehicle not in the same category? And why, on the occasion when people are caught doing it, do they lash out so violently when challenged? As if somehow it's their right to damage your property, and you're somehow in the wrong for catching them doing it?