Is Trolling In Normal Games OK?

i have seen a lot of people intentionaly feed in their normal games and i myself have done it too,everyone talks about toxicity being leagues only problem but what about trolls? how can you expect a player to not flame when you put him in a situation where he can be griefed by another player for AT LEAST 20 minutes? I persoanly remain calm at all times,i tolerate players who play badly,everyone has bad games. i tolerate players who flame,maybe he is on a lose streak but i cant find any space in my heart for trolls,and how could i? how can i respect someone who finds joy in making everyone sad? this isnt a rant,or a saltfull thread,just a reminder to riot that flaming isnt league's ONLY problem.