Bumping this thread.
I thought of Timmy from The Fairly Oddparents, but I feel that Timmy's case is more justified. I would be a jerk too if my parents always left me with an evil babysitter and the world treated me like I was a waste of space. I would be an asshole too if my teacher was always stalking and bullying me and it doesn't help that the episode "It's A Wishful Life" was a big middle finger to Timmy. Timmy has every right to act like he does.
edited 15th Jun '15 4:25:30 AM by MsCC93
Oddball Nerd
So then he would be a 1.
"Detecting trace amounts of mental activity. Possibly a dead weasel or a cartoon viewer"
useless legacy
A jerk character can often function as a Character As Device, being one way to keep the protagonist(s) grounded. For example: Alexandra Cabot from Josie And The Pussy Cats.
It'd be easy for Josie and company to edge into Mary Sue territory without Alexandra as the Token Evil Teammate and her tendency to be The Load. However, Alexandra also receives plenty of Laser-Guided Karma that makes her the Butt-Monkey on the show. And though she's subversive, Alexandra won't cross the Moral Event Horizon by outright hurting Josie; she's aiming for humiliation / embarrassment, not pain or bloodshed.
Thus, Josie has to deal daily with The Starscream as part of her entourage, which keeps her out of Mary Sue territory. I suspect that many Jerkass characters exist for the same reason.
And for what it's worth: though the cartoon never really explores it, the original comics do: Alexandra believes that she is the all / the it / the everything because her father is a billionaire tycoon who believes his children should be as magnificent as he believes himself to be. Her ebullience is the result of being browbeaten toward greatness. Josie keeps Alexandra as a friend because she's a pretty decent girl when she forgets that she's a Cabot.
I always thought Roger was very strange, and I never liked him. not because he's an asshole.