I have had the same experience in both this leaderboard and the last. A couple of my friends and I have been charting our spinning results and have come to the conclusion that highly ranked players recieve the lowest point chests. S8 claims the results are random, but evidence seems to show that is not the case.
Oops- forgot to include my info: I've been running in 2nd or 3rd place this event and have received nine 25 point chests, one 31 point chest (leader was boosting at the time), one 47 point chest (leader was boosting at the time), and the rest were either trees or coins.
In the Tropic Tide leaderboard, I ran in and finished in 1st and got all 25 and 27 point chests and a ton of palm trees. No variety, at all, on the number of points in the chests.
In the Mama leaderboard, I finished 1st and never dropped below 3rd place, but I recieved a wide variety of points in the chests. I think the change was implemented when they added the 200+ point chests to the event.
(I've been fortunate to be placed in laid-back leaderboard groups so far, and have been able to do pretty well without spending a lot of gold, just a couple here or there to speed up hatchings. This time, I will not finish in the top three because I quit actively participating when I reached my goal of the Sparkler, so I am very interested to see how my chest points will change as I drop in rank).