Smalls, they attacked a KID - a high schooler. That alone should be enough to get them fired. Secondly, if Entercom didn't fire them, they likely would have faced a bunch of angry advertisers, along with a group of activists who simply wouldn't let the issue go quietly. All of that negatively impacts the bottom line.
These dopes aren't Stern. They don't have the numbers or revenue that can withstand that kind of downturn. If they've spiked their careers, it's because they don't have a body of work that says "This was an oops, but they're really good broadcasters." If that was the case, somebody else would scoop them up in another market. That could still happen, although I expect that they won't go as a team, and there will be a cooling off period.
BTW, there IS life outside of radio, and anybody who does this for a living really needs to consider other options from time to time. It's also pretty clear that there are a lot of good, experienced people on the beach who WON'T do 12 minutes of bad radio, and WON'T piss off sponsors and activists. K&B needed to keep THAT in mind before Kimberly lit the match, then threw on the gasoline.
In case you haven't been paying attention, intolerance of other peoples' private lives is OUT. Health care is a muddle at best, and negotiations between municipalities and unions are a minefield that smart broadcasters probably need to avoid. There are plenty of other topics that are much more universal. Somebody thought that they'd lay a little smack down and get people talking. Well, they did get people talking - mostly about what morons they were to pick on a high school kid ON THE AIR.
Even Lonsberry, who's got a LOT more pull than those two, got smacked for the remarks on his blog. And he didn't even attack a kid.