Why do I get less for more?

So on the leaderboard for the gears 5 escape map “The Hunters” it has rewards such as Top 50% get 2,000Xp while top 100% get 1,000Xp this is nothing wrong but when I go a stage higher at top 10% you only get 1,000Xp like wtf why am I getting less for being better?

You get all the rewards at your tier and below for escape, but it does seem weird.