XSET: played well, had a disadvantage during the round, accepted defeat, riot told them to replay, they complied
FPX : won the tough game,were very happy, 2 am in turkey probably were gonna sleep, get told to replay the round thereby risking their tournament run , they also comply, win again
misunderstanding (most probable) : they might think that someone from the XSET team did call for the rematch and are hiding it which might explain the angry behaviour, the other reason maybe they thought xset should have called it while they were on stage instead of 1 hr later(which i don't think xset were gonna do since it looks like they accepted the loss), Riot isn't doing a good job either by staying silent.
The regional fans: posting 100s of posts each either focused on hating XSET or FPX, which furthers the hate which is already a problem here.
if you haven't been toxic about this you are a lovely human and for all these toxic post spammers and baiters: grow up !