Honestly, I'd be less annoyed if people will report for literally no less than me going "I dunno if Kog's a good pick, we have no peel" or "I dunno if an Akali top versus a Cho'Gath is a very good idea." It's their champ. And half the time their champ is far worse just in general.
Yeah, the joke that Teemo's the worst champ and the troll champ is funny. Haha. Cute. But you don't then end a game with people blaming you and only you for all of their fuckups, feedings, misplays, miscommunications, failures to communicate, and absolute lack of ability to do their jobs. It's cute as a joke, but when you get reported - reported - for telling your team to stop being assholes about you being a champ that is the sole reason the enemy hasn't overrun the base and that we have any objective control at all, the joke's done. That's a bunch of dickholes.
Like the only reason I ever go Nasus isn't because he's fun - it's because then I have an excuse to not have to deal with any of my teammates for 30 minutes. Because AFK farming is "Just what Nasus does".