Fortunately in my immediate area there are more than enough courts to go around. If you show up and and the courts are full, you can drive 3 minutes down the road to some other courts.
Because of the plethora of courts, we generally do not have time limits imposed.
However, at my regular place ... if someone was using a court alone while others were waiting, something would definitely be said. And I can almost guarantee that solo person would pack it up, or end up being included with those that were waiting.
"You should be playing linebacker, not singles."