Yeah, I can’t imagine how awful some of the remaining parents must have been that so many families felt compelled to leave right in the middle of the season.
Parents and players should always honor their season commitments (as long as there is no abusive behavior from the coach/club), but when that season is over it is nobody else's business but theirs what they are considering for the next season until that decision is made. That is also true for the coach, club and teammates. Don't tell lies and if it is time to move on, move on. As Surf Zombie says, look out for what is best for your player, but remember that includes setting a good example in honesty and honorable behavior.
I don't think this was the "middle" of the season. Sounds like the season ended in November.
Tryouts took place all over town during December and January. Players made decisions to leave.
State Cup was to be played (I assume this is an 06 or younger team, but could be wrong) in February. Did these players bail out of state cup?
"Technically" the year you pay for ends when State Cup is completed. But clubs hold tryouts as soon as the fall season ends.