Rubbing and small contact I'm OK with. Well I'm not, I don't fully understand why contact between cars is necessary. Either you can make it clean and do it, or you're unsure and wait for a better moment. But I will say it's understandable. I'm not a prude who thinks that races will never have contact. They shouldn't, or at least wouldn't have as much if people were more careful and cautious, but that's beside the point... I can live with you tapping the side of my car, but if it's persistent, there's a problem with your driving, not mine.
Intentional or not, negligent driving isn't something I tolerate, even less so when I know the action was deliberate, but it's in no way acceptable regardless. I know, accidents happen, they happen far too much, but they do happen. I wouldn't hold you too accountable if you'd just make an attempt at making amends with myself and other drivers. Maybe even just write their name down and send them a short message detailing your intent and what actually happened.
Earlier this week I was rear ended on Suzuka at the turn after the hairpin (roughly halfway though the course...) I don't think the guy did it on purpose. He seemed clean and legit, and we were neck and neck coming around the bend. Well he pulls behind me, and when I go to brake, he smashes into me. He had little to no room for judgement, or just poor reaction time and hand eye coordination, and managed to find himself in an awkward position which ended up with me in an even funnier spot... in the sand... My braking point is much earlier than his was, apparently, and I have to be careful with the Vette. I've drove Suzuka so many times I know where I'm comfortable and what speeds I'm comfortable with, and I feel safer at the point I brake at. Now he might have been trying to push his luck, or maybe he could pull it off, the possibility that it was on purpose is there, but I'll give him the benefit of the doubt. Naturally I was upset, but I wasn't so much pissed that he did it, I was more angered by the fact that he drove off and appeared to care less.
This is the type of etiquette I'm talking about. If you're going to push your luck, so be it, but if you screw someone else doing it, and innocent driver, don't just shrug your shoulders and say "Sucks to be him." because then you wind up blacklisted and being targetted yourself.