The amount of time the Highschool age kids are playing throughout the year gets relentless. If they play Highschool, they only get a short amount of time for rest and vacations. That is the second half of July and August, a couple weeks near Christmas. Besides that, they are playing League and attending League Events September into early December. Highschool has already started in December, so they immediately start playing 2-3 games a week into February maybe March if they are in CIF Playoffs. Then straight into the League Spring schedule through Late June to July. I don't think most of the higher level teams have any interest in joining summer tournaments. Most of these teams are likely using a couple summer tournaments to try roster changes/movements with any new additions they have, and tune up for the beginning of League.