I agree riot should let you do something with your RP, after all, you did spend money on a product and now are being illegally denied access to money you've spent because somehow you broke riots failure of a justice system.
For one thing, riot should ban more people than they do based on metrics that I have observed through personal experience and observations. No one knows that saying "report elise AFK, or report Thresh spamming, or he called me a n**g Je*" all will get you banned under their failed system.
Hell, the system doesn't kick back false reports like it should. I just got out of a game where I didn't type anything in the chat throughout the pre-post except Jungle and I got a pop up saying offensive language. As a player who's trying to change his toxic ways this is disheartening to see that now my account is being flagged to be looked at even tho it's a false report.
So, in short they should let you spend RP you just purchased even if your accounts banned, not on yourself, but on your friends because their system currently is NOT working as intended.