Let me tell you something. For any reason almost everyone, if not actually everyone, has left at least 1 game. Be it because there was a power outage, network fail or other issues. It has also happened to me to leave some games now and then for reasons, though never intentionally. But, you know, if you leave one game you dont get a leaverbuster, at least the last time it happened to me i didnt get. If you keep starting games, knowing you have a network issue, and leave cause internet shuts down, its 100% your fault. And seriously, you expect RIOT to allow you to ruin the game for other people simply because you cant understand that you should fix the problem instead of blaming others for giving you what you deserve, especially cause, seemingly you dont intend to accept your mistakes?
Plus, this is their game, aka their rules and you agreed to those rules. You cant blame them for enforcing them.