Masters Promos and people leaving.

2 out of my 3 games to my promos to masters, I've had both two games where there is someone who just quits and never comes back. Does Riot even care about this? Are high tier players immune? What the fuck is this? I keep seeing the same player who leaves the game just playing.. not a single fucking given because Riot doesn't care about banning players who leave/afk in this elo? This is COMPLETE FUCKING BULLSHIT. This company is just falling apart now? So many fucking issues going on in this game and I have not seen any improvement. This is beyond frustrating.