[Bug] 4/7 game with Trolls/Greifer who afk throw and quit

I mean either Riot's out to screw me in the ass, and really want me to be at 50% winrate, or there's some awesome BUG that puts these children on my team who literally at champ select grief, get killed once than quit. today alone 3 of those games out of 4... like.. why Riot? Why is there not a system to perma ban these people, or not screw the 4 other people who are playing?

I mean when they literally say "have fun with your lost" at champ select... ffs get ur shit together no wonder the population is dying.