I find it helps to imagine a ZK team game as being an in-person game of sports ball.
If your contribution to the team is to go and sit crossed-legged in a corner of the pitch instead of playing, you'll probably find that your team mates not only remove you from the game, but don't invite you to future games.
Yes, it is your god-given right to sit down on a playing field if you feel like doing it. But it isn't anyone else's imperative to include you in their team sport if you fail to abide by the conduct of the game, so you'll end up sitting on a playing field by yourself and not included in the game of sportsball.
This is super intuitive and obvious in person, and yet when people are alone at a computer the domain-dependant understanding of basic social cues in a team sport does not always seem to come easy. I guess it doesn't help that RTS games attract a certain.. spectrum of players, who do not always find social cues so easy to read at the best of times :-)
For occasions when you don't want to abide by the conduct of a team sport, and just want to sit on the field or dig a hole, there are very functional bots.