You imply that AYSO referees, because they are volunteers, are not well trained. You should look into that before making such statements.
I've been through both the AYSO and club ref training. As I stated before, the initial AYSO training is just better than the club training and AYSO does a lot more to support people as they go along. That said, AYSO forces the parents on teams to volunteer to referee. As a result, as a new CR my biggest struggle was bringing along ARs that hadn't read the material and didn't really care because they were just doing it because they had to. In fact, I went out of my way to try and work with youth volunteers because 1) I really like working with the kids, and 2) unlike the parents, they knew their stuff, even if they needed some encouragement to make the call. Some volunteers just didn't care, wanted to do the bare minimum out there and the bare minimum of games, and unlike club refs didn't have a monetary incentive to do the work.
Both things can simultaneously be true: 1) AYSO has a lot of good experienced refs, particularly those with a higher than intermediate rank, and 2) AYSO has a lot of newbie refs, some of whom don't really want to do much more than the bare minimum