In the spirit of trying to see all sides of the issue...and to perhaps cut the "average" parent a bit of a break; that parent often has to pay the hundreds and even thousands of dollars in orthopedist bills as well as secondarily potentially being a bit concerned about their child's health -- so the yelling in a very physical game might represent a primarily financial as well as a minor tertiary personal concern.
I'd like to see three referees -- but more than that I'd like to see some (not all) referees stop letting kids ride other kids like horses and make a call without needing the evidence of a trail of bloody viscera on the field.
