> By the third or fourth season, the parents that had started with me would help wrangle some of the other parents

This is where we were with one of my kids' teams. Once they got older and split into the elite-national/regional club level (about U12), the parents were not healthy. Over time, the parents started to realize that their kid wasn't likely to play D1 college soccer, so there wasn't a point in being "those parents".

It also helped that a few of us that either coached, played, or ref'd would "help guide" the other parents. It is now to the point where I wouldn't want my kid to change teams because our parents are so awesome.