Kitersurfers who are over eager and "Rush" to the beach even though everyone knows the wind will not be up for another 2 hours. Golden rule...Go kiting when there is wind and pack a surfboard as backup.
Preachers.... and they tend to be more in places where there is less wind!
Sydney... It is tough kiting here. I moved from Cape Town to Perth and now Sydney. CPT there almost too much wind and quite big swell. Perth has awesome wind and warmer water, but the waves are small (except if you travel). Sydney has the most inconsistent wind forecasts making it difficult to plan weekends away. On the upside, I probably enjoy kiting now more than ever as you really appreciate it when there is wind

There are some good wave spots in NSW.....
Kitesurfers riding between surfers... just do not do it. Accidents can happen very easily with +20 meter lines. No point in p.... off the surfing community.
Twintippers trying to ride waves