Why are challenge rewards the same at different higher rolls?

Forget the fact you only get one die reward when rolling multiple dice, I would like to know why the same rewards for gold and gems are at higher numbers on other dice?

Example if you have 3 gems and 50 gold on a 1 through 6 theirs no reason for it to be at like 7, 9,11, 13 etc.etc. or having same rewards right next to each other like 500 gold at 13 and 14.

Would love a response to why this is there.

I understand why from a developer design it’s like this but with every other ( community will say issue, problem, developer will say design) thing the way it is you really had to go here as well?

I also don’t think anyone really wants a higher % chance to get 3 gems or 50 gold that don’t stack.