Me too, first turn out is the start of the kill zone for me. Sometimes someone doesn't turn, and that's their mistake not mine. Although if it's a relative noob I will text "hey xxxx turn hard to evade!" in an attempt to coach. As soon as they respond F Off, they are mince meat
The spawnpoint is a kill zone for me only in BTB and BTC when incoming with a bomb. ESPECIALLY now with segregated servers.
One time I did get on someone for sheer kill mongering in Shoot Zepp. I was defending the zepp, and this high ranked red on the Kill Zepp side flew right past the blimp to my airport and spawnkilled my teammate, who was a little green and wasn't on the brakes. My teammate threw out a wtf? and I replied "yeah xxxx does that" because I had seen him do that a few times in other games. The high ranker didn't appreciate the callout. I mean, are you so desperate for K/D ratio that you fly PAST the blimp just to hit a level 10 on the runway? No bomb, and as for the mission, umm, you kind of blew right by it.
But like you said, it's all part of the game, it's all legal and certainly not bannable. If Z wanted this game to be a series of Atari bombing runs, he would have programmed it that way, but guess what, we have the freedom to fly around an entire airspace.
Manfred