SPOILER -Maybe the kid didn't get comeuppance because he WAS comeuppance

The kid was a little douchebag, but...

The bus driver was awful to his passengers. As a result of the accident that the kid caused, the driver was not seriously injured but he was fired. The passengers he was terrible to probably got settlements (as mentioned in the movie).

Despite what the kid did, the (former) bus driver chasing him in a car, while the kid is on a bike, was incredibly dangerous and irresponsible. He's lucky he was hurt and the kid wasn't because his life would have been over (instead we just get to watch barroom wheelchair racing).

The boss at the end probably gets into an accident too when mini-douche throws a rock at him. He kinda deserved it.

And the mom did NOT deserve to get egged, obviously. But because she was, Sally ended up on the "telly" instead, which is why she finallyl figured out her 'stache problems, which she then mentions to Oscar, who tells her that she just needs to bleach it. Then they have coffee and end up together.

Just a thought.