Usually, no students complain directly to their teachers at school.
However, some high school soccer players complain about the referees.
At that time, I give them a long lecture even during the game.
Referees may make mistakes.
But I think it's the fun of sports,
and the judgments can be disadvantageous to us but also advantageous to us.
So, it's only selfish to complain to the referees.
Moreover, the referees are volunteer teachers.
I think, this is also not humane.