Intentionally feeding yas

So I was playing ranks doing great and all and this yas in my game decides to intent feed MiruMaru is his username. he fed my last ranked game while it shouldve been an ez game for us. but tahnks to yas going 0-7 early game and NOT GETTING BANNED is just amazing move. I know I dont make great decisions and still lack talent but this is complete bullshit. I get banned for swearing but CLEARLY this is a R rated game apparently and people that afk or feed dont get banned. I have not once seen any one of my reports get banned. so riot is just a childish ass game