Easy answer. Some parents want their kids to have an advantage and think they are the best parents because they will do anything to better their kids' chances or experience. They don't care about anyone else or fairness. It's justified, the kid is better in high school because he got all the training and all the game reps. Some kids hold back or even double hold back on top of this. Lacrosse allows it. So the parents do it because there is nothing to stop it. Most of the other sports don't allow this. It won't stop until the sport won't allow it.
Not sure what information you’re getting but there isn’t any difference between high school sports. They actually all follow the same rules. There are plenty of basketball and football players doing it. And for those parents who continue to use the “injury” line, if you’re putting your kid out there and you’re concerned about their well being but still putting them on the field, you’re a pretty lousy parent.
