I believe hockey teams have a binder that has each kid's Hockey ID and a team roster that can't change every tourney (or mid tourney). Makes sense as does the age thing. That said most hockey players go to juniors before HS so they enter HS at 20 or so, but it is expected. You are allowed to play up but not down. All in all it makes sense, is consistent and is fair. Right now lacrosse has gotten off the rails, there is at least one large national club with regional and national teams that plays musical players so they ensure wins. A few of the kids are playing at two age groups claiming they will take a PG year when they play down. | 
