Why are int feeders never punished?

to avoid naming and shaming i will just post the evidence of massive int feeding and trolling taking place without showing the name of the culprit.

https://i.gyazo.com/524ab2f52955bf7ee92384016bc0f28e.png so the guy has a 2% win ratio on nunu which is 5 times smaller than what you would have by playing 4v5 every game, is he int feeding? yes obviously. has he done it for a long ass time? well 250 games of int feeding should get you banned no?

now if you say anything negative about this guy while his doing his standard int feeding you will get punished and he will be completely fine, rito pls.