Penalties for impaired players?

So I recently had a game with a player who was high, as he so loudly announced through the use of all caps to let us know he would suck. And honestly he was one of the main reasons we lost, he would rarely gank, and when he did it usually was at the wrong time and he would go too deep and die, or would get into fights in river and then keep fighting for a bit before realizing he should run, usually resulting in his death. Now this is not the first time I've dealt with players like this, nor do I imagine it to be the last. And whereas I'm sure a lot of use have played games impaired in one way or another: be it alcohol, marijuana, or simply major lack of sleep, it does still beg the question, is this ok? For whereas the players may not always feed, if they do nothing but meander around the map and react at a snails pace to the events of the game, the end results are usually the same. I doubt for example a pro player would be allowed to show up to a tournament drunk or high, and most will probably agree that playing in a severely altered state of mind is not fair to your teammates. And isn't the reason we penalize actions like feeding and being afk because of the negative effect it has on the other players. Not sure what actions if any can or should be taken but I will say I think it's something that might merit some thought on Riot's part, and I for one I'm quite tired of this occurring as it has ruined many a game for me. Thanks for the read, would love to hear Riot's take on the matter.