I'll start by saying that I am only an average player, honestly probably below average if I didn't have the advantage of a very good team. So when my opponents quit 8 in a row, and then next day 5 in a row, it is out of control. Given that I haven't quit one single time all year, maybe one time when my power went out, I would think that EA would at least protect me from these losers. Apparently not. It's not like it is a huge programming challenge. I understand that rep systems can be manipulated, but quitting is objective proof of someone misbehaving and already tracked by the game.
The only other possibility I can think of is that everyone at the same ability level as me is a quitter and I'm the weirdo that plays on even if I'm down 2 or 3 goals.