bainsey wroteWhere else would you allow them? It's a little cramped along the sidelines.
It all depends on the size of the gym, the unobstructed areas around the court, and the safety of players, and the officials. It will vary from site to site.
I once had an adult fan standing against the wall on the endline of a very cramped gym. He kept getting in my way as the lead. I asked him to please move over to the side. He replied that he was the school's principal and that he would stand where he wanted. I countered that I was in charge of the safety of all the participants, including the officials, and that he should move. He moved.