You are also correct. This is where the expectations of the players, coaches, and parents all come into play. Some of these people are simply happy that there son or daughter is playing a sport and having fun, while others (normally the more skilled players) are looking for more. These players only have a few options depending on the size of the program they are participating in: 1) hope that there are enough like skilled players with parents and coaches that are going to demand a commitment so that there is enough to field a team with the same high expectations and skill level. or 2) go to another organization which supplies what they are looking for.
People on this board need to stop placing the blame on parents and players, and start looking at the organizations, coaches, and hockey directors that are not doing enough to adequately serve this portion of their "customer base". As with any other business or service, if a customer isn't getting what they want, they have the right to look elsewhere. Successful businesses don't blame the customer for leaving, they try to find out why they are leaving and make changes to address what the cause is. If organizations within PAHL began taking this approach, there is a chance that we could be looking at stronger teams at the AA level but until people in the hockey community start to look at what is causing players and parents to look for other options instead of jumping to the "they think their kid is the next Crosby" argument we are going to be forever stuck in this cycle.
As for the "trickle down" where there's the perception that there are players on a higher level team that shouldn't be there because player's A and B went to another organization to play, the answer to that problem is simple... The players who are moving up into those spots need to simply get better.