This is exactly what the enemy kassadin player said to me in my last hide and seek game (if you don't know what it is, then basically 5 hiders have to survive for 40 minutes and not get killed by the 2 seekers 5 times; the hiders can only use cc abilities and can't go back to base until they die; when a hider is out they cannot interfere with the rest of the match and must stay in either their base or on the outer ring of the dominion map).
He wasn't the only troll, as leblanc and kayle kept trolling by attacking us and capping points when they were out of lives (kass not only built sunfire cape, one of the banned hider items, but also kept ignoring us and cussing us out (I played as seeker sion and my partner was malphite). The kassadin even kept spamming "qq" in end-game chat and also even said "i play trundle" "Im a troll" and the kayle also said "I'm reporting you for negative attitude :P" even though she was trolling by capping points and helping the remaining hiders (i.e. kassadin and kha'zix, the other out hider was lee sin).
What I got was that this kassadin player thinks that because it's not an offical game mode made by riot that they're are no rules. Just because it's not made by riot doesn't mean that you can act like a troll, do whatever you want and refuse to listen otherwise (this is primarily why I make my games with the tag "(no trolls/cursing)" in hopes to weed out those players and yes, I've have had some players join just to cuss me out and either leave or get kicked by me). Either play by the rules or just don't play at all please, it's just that simple.
Thank you for your time.
P.S. For those of you wondering what the match was like, here's a video link showcasing the match: http://www.leaguereplays.com/replays/1247320