Hockey is an expensive proposition regardless of the program. Different people are looking for different things out of the sport. Even on the same team you can have a family who is all in on the sport and another one that looks at it as just one of many activities. There are also a lot of differences between the programs in terms of the amount of ice time and off ice training the program involves, as well as the amount of travel and associated costs. 20-25k is more like AAA costs.
There is a lot of fluidity between the divisions, but in general, AA is a faster brand of hockey than A, which is faster than BB, which is faster than B. There are all sorts of circumstances involved in whether or not an individual kid could easily play in a higher division. There are kids who would do well in AAA playing in AA and A most likely.
But there is no doubt in my mind that the average skill level of kids in AA is far higher than the average in A. All you have to do is watch some games back to back to see the difference. As to whether in the long term that difference means much is hard to say, but in general the kids that play in AA stay in that division or move up to AAA, or go to Prep school, while the kids in A often move to High school as soon as they can. LAKSHL JV from what I've seen borders on in house level.
Kid who played AA are better prepared for the speed of the game as they continue on to higher age groups, but certainly it is true that kids who never played AA before Bantam are able to acclimate to AA as time goes on.
I watched a period or so of a Bantam A game last weekend just prior to an AA game. In both games, one team trounced the other. In the A game you could see that some of the players on the better team were talented -- in fact it was quite obvious because they had lots of time to deek around kids and make moves around the net that showed off their skill. In the AA game there was also some skilled plays, but very often the defensive players reacted and the goaltending was substantially better.
Even the losing team would probably have beaten either of the A teams soundly, which is the problem that a lot of teams face when they are a bit too good for A, but not really good enough to be competitive in AA.
In A you can stay competitive with one really good line just by pouring in goals. In AA team depth is far greater, and opportunities to handle the puck along with goals are much harder to come by.