The easiest way is to get to know the people you are riding with then it is easy to discuss this kind of thing with them, I have never seen any attitude in nz kitesurfing all good people
kiters hurting each other has nothing to do with potential bans (whoever heard of a kiter going to the authorities about another kiter - that will be a sad day indeed..), it is total respect for non kiters in the kiting area and not going anywhere near the red and yellow flags (swimming zone) that will keep things sweet.
Going somewhere like Ruakaka on a weekend after 2 weeks of no wind may not help - it is small and there are soooo many other places to ride with no one else around - nowhere else in the world is lucky enough to have so many spots to ride within an hour and a half's drive
The rule for me with riders that i can see are learning/learners is keep well clear at all costs until they have full control at all times and understand the rules of the road (can handle big gusts and have full confidence) - kind of why I would not go to Ruakaka if I knew there were learners there as there is not much room for error, liekwise learners may want to think about finding a less crowded area for faster progression.
unwritten rules
use common sense to keep riders safe irrelevant of any other unwritten rules - ie if you see some traffic jam potential turn around before it happens
downwind - keep your kite low as possible
upwind - keep your kite as high as possible
if standing in the water or at the edge of the beach with a kite in the air this also applies - or you will stop the flow and everyone behind the person you stop from going past will have to turn around too and you create a hug traffic jam.. (especially with onshore winds) These riders have a special nickname
When someone is coming towards you try not to tack right in front of them unless you have no choice (tack very early or better still go pas them) - keep spread out as possible - it is likely that the person you tacking in front of is saying to themselves "well thanks a lot, now i can't do any jumps/ tricks cos you are in my way - and this is the 5th time in a row you have done this to me, goodbye, you are the weakest link"
On waves rider already on the wave has right of way - if you are heading out through teh waves - keep out of their way - easpecially important in bigger waves
as far as riders trying to pinch each others upwind spot starboard does have right of way if you are on a collision course, but this is quite rare it is usually very clear who is further upwind so give way, as you kite more you get to know all the tell tale signs of someone trying to communicate to you that they are more upwind than you when they are in fact full of shit lol! ?(they come to a grinding halt trying to point up wind too much.. More skilled riders tend to end upwind also as they often have better upwind technique.
Take this all as a pinch of salt just trying to explain some stuff the best I can to newcomers so that riders have a good session and don't end up pissed off.