From the perspective of the players and as a high school student, I personally don't see why it's such a big deal, it wasn't done on school time, it was privately funded, and we are indeed able enough to make decisions without the consent of our parents (that doesn't mean we always make the right ones.)

That raises the point where you might say, "Could be rebellion," or some such but that brings up the question of whether or not they they were truely committed in the first place, making any decision out of spite and or rebellion just that, a  non-commital, non-weighted conclusion by the teenager.

On top of all this, it's not like this is the first time a sports team has been taken to a church and it only becomes unconstitutional when it's forced on them,  It's not like "you must be baptized or you can't play." I rule, "let em go!"