It's clear ! Promo games are intentionally made harder to win

I can't comprehend how me and 219748139856 other people seem to think that whenever when you have promotional games , your teammates suddenly go full retard.

It's been the 314861 promotion in which my teammates just suddenly go full retard.

First game one dude feeds and goes afk because i didn't gank his enemy laner LeBlanc with my Rammus. I wonder why ...

Second game i get a jinx adc that says after the game starts that he's high. He then gets mad at our shen for failing to block a caitlyn ultimate that was going at her and then she started feeding and going afk saying she wants that shen to lose.

This is bullsht . Just pure bullsht. How am i supposed to climb the ladder with those kind of monkeys in my team ? How am I supposed to keep my calm when this happens ?

And most of all, how are those players still allowed to play this bloody game ? It's clear by their attitudes that they did this before and that thy will do it in the future. Why are they still allowed to roam around ruining other players ranked experience ?