Why is not trolling and intentionally feeding ban-able

I lost 2 games where people were trolling like 2/16 bot and 3/10 1st game second game afk 1/3 top since min 6 and a bot 0/12. And they will not be punished for that one of the admitted he was actually trolling. But when i say to chat please report them for trolling everyone keeps spamming enjoy ban and i will report you, you are toxic. I don't see how when people ruin the game they are safe but when says something obvious like "Please stop trolling and feeding" is being punished for "toxicity". I m stating a fact. You ruin the game for me and the team you should be punished. It seems that Riot has focused more to Public relations that the game it self.
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