There are many who seek knowledge for the sake of knowledge: that is curiosity. There are others who desire to know in order that they may be known: that is vanity… But there are those who seek knowledge in order to edify others: that is love.
I agree with AKradian on this. All medals should be added to the medal collection and stay in the collection. All they have to do is make the time-limited stats ones not renew the stats when being re-redeemed from the collection, and would still give incentive to redo events like SadVirgin said.
But hey, on the bright side at least you got a response, other issues have yet to receive a recent response (that I know of).
Honestly it seems this game has more issues than National Geographic has magazines. (Humor.)