Useless mastery tokens

Hey I know this is a bit out there but I have a couple of mastery tokens in my hextech stuff that I really don't want. I don't feel the need to get level 6 on any of my champs and I also never get any blue essence (not complaining about that though). I had a thought, what if we could turn spare mastery tokens into key fragments? Then you could reward players more for rank S's and make them strive even more to get gud. Just an idea. Luv u riot!