Poor sportsmanship happens in almost every match, but on topic with this thread: just leave and add a win. They probably will add a win too, but they already have a fake record.
Most reasons of people giving up, is cause they know they will lose badly, and figure 'well we will lose might as well have fun' or 'they FF'. But the reason of this could also be, if they lose 50-0 or something, they will get harassed with screenshots of how they suck. So it works both ways. If a clan is respectable, plays and loses then don't brag and post screenshots. But you have often come on vent to talk crap to many people, so you ever think you could be part of the reason? Although you haven't done it for a while, you use to do it alot, not that people took you seriously or cared much.
Don't match them if they wanna be idiots, but then again with only a few clans out there.... hard to do that. Also, alot of people ban everyone when they lose, it's part of their raging. If you say: addloss? or anything, your gonneee!!!