There is a well understood relationship between running economy and small changes in shoe weight which lead to important changes. So even if shoe weight had no

There is a well understood relationship between running economy and small changes in shoe weight which lead to important changes. So even if shoe weight had no important impact on jumping performance it will save significant energy over the course of a game to shave even grams off of a shoe. The reason for this is running involves accelerating the foot, then decelerating it, over and over, and the shoe is at the end of that pendulum motion. Not to mention lifting it against gravity as well.