Riot bans you but lets people who say KYS keep playing

Just had a very rancid game where player threatened to leave game if I didnt gank. Then proceeds to tell me "KYS." I get very frustrated and talk back when I lose my cool. Throw in some cuss words, oh NO! He continues to say KYS over and over. When reports are in, I get punished but I'm pretty sure the guy is still playing. Thanks Tribunal, blind banning with no context to back it up. This automation is just sick. Like punishing people who kill in self defense. Very sick. FYI riot, KYS means kill yourself, and FYI means for your information.