Rune Page Editability for Players with Max Rune Pages

Essentially, i completely understand the purpose of having us buy rune pages, Riot needs to make money i get that. I personally have the max allowable set of rune pages, but on occasion i may want to play a random champion outside of my normal pool. In that situation it would be very convenient to modify my rune pages. The main complaint i see about this feature is that people will stop buying rune pages. If you add this option as an incentive for unlocking all rune pages, it would cause more people to purchase max rune pages, and make more money for Riot.

TLDR: Add the ability to edit rune pages in champ select for summoners who have all 20 rune pages unlocked.