First of all, one would like to think that a coach who has kids fortunate and talented enough to play on some other teams during the summer two very important things can and do happen: 1- For the talented kids playing on other summer team's they face most times better competition, see lots of playing time, learn things that perhaps they haven't yet on their HS team, and the untold potential growth this will mean for the player AND for the HS team the next year, and 2- those players who DO stay around home during the summer but play ball and are maybe your "average/bubble" players benefit by more playing time because the others are off playing summer ball elsewhere. It gives a coach a broader and deeper look as to what he has to work with next year and maybe see where some of these players could best fit in. And playing time is where this is done at. It's not about winning or losing during HS summer ball. It's preparing for next year. Top tier winning coaches know this.
With all that being said, I know in Georgia and perhaps most states that if a Coach makes such a statement about any player who doesn't play for him during the summer faces being cut can be terminated. This was the case up to just a few years ago here so you may want to check on this. Your HS Athletic Director is one place you can find this out with. Or your local County Commission. They take this stuff pretty serious.
You just hate that it would ever get to this. smh
YGD