I have coached for several years and have had to deal with parents complaining about playing time. In a perfect world everybody would get to play. In a perfect world everybody would always make it to practice with great attitudes, have great ability and give great effort. We don't live in a perfect world. Life dosen't reward not showing up or showing up lazy with a poor attitude.
As long as we keep score, coach's will try and put their team in the best position to win.