I’ve had jobs where I was paid a pittance of an allowance to be on-call. During these periods I was not able to enjoy a few drinks and often couldn’t participate in social gatherings if they were too far from my workplace.
I don’t think it’s asking much for highly paid professional footballers to sit out these amateur competitions or other sports with a higher than acceptable risk of injury, particularly HIA’s.
In relation to the Koori Knockout, I see no problem with professional footballers attending the tournament as an ambassador or for promotional purposes.