PreGame Trolls and pregame leaving punishments

this happened in a normals btw. i got into a pregame lobby were i called mid three times in the same sentence and a guy got mad?,over me saying mid three times in one sentence and said you spammed mid therefore i got mid he autolocks yasuo (even tho i got mid).So knowing this guy was gonna be a negative douche bag my friend left and he got punished like what the french . . The fact that you get punished by staying with a troll and losing or get punished by leaving 5min timer + /and or chat resrist bann etc.So i just wanted to put this out there that this is not fair and need to be fixed