I couldn't agree more. It doesn't matter what team your son is on. If the talent he's playing against is as good or better than him, then he's going to improve. The goal is to allow your son to grow and develope as a player. Which is better? Having your son on one of these super teams, where he plays 30% percent of the time and watches 70% of the time? Or be on a team that may not win all the tournaments, but you son plays a lot against tough competition. He will get better playing more, against tough competition.
Believe me, if your son is not one of the starting 10 with one of these top teams (AA or Elite), he's not going to play that much. It is not pay for play, it's win at all cost. The cost to you is your $1500, and the cost to your son will be extreme frustration.