Almost overnight, he went from King to quitter.

When LeBron James announced that he was leaving his hometown Cleveland Cavaliers to play for the Miami Heat, some fans reacted with a little heat of their own – torching LeBron jerseys.

"Instead of throwing an ex’s clothes out the window, they’re burning his," says Annemarie Farrell, a professor at New York’s Ithaca College who teaches courses on sports consumer behavior and fandom.

Farrell compares James’ hyped ESPN announcement of his decision Thursday to "breaking up with your partner on CNN while the whole world is watching."

It felt cruel, she says, and that’s what fueled fans’ feelings of anger and betrayal – common reactions when a valued member of a team decides to leave, says an executive recruiter.

You could see it in Cavaliers owner Dan Gilbert’s open letter to fans, in which he called James’ departure "a shocking act of disloyalty," says Bradley Richardson of Kaye/Bassman, an executive search and recruitment firm based in Dallas.

"No matter how much you’re one of us, the moment you resign, you never were that good anyway. When people resign, even for the right reasons, it is personal to the employer, and there is always revisionist history."

It was revisionism at work when Gilbert complained that James hadn’t tried his hardest during playoff games against the Boston Celtics. If James had opted to stay in Cleveland, "would that have come out? Absolutely not," Richardson says. "That’s petty. That’s sour grapes. That is the jilted lover speaking."

And in today’s business climate, jilted lovers abound.

We’re a free agent nation, says Robin Bond, a Philadelphia employment attorney.

"The whole concept of the company man, the person who was totally loyal to the employers and wouldn’t even think of leaving the company, started disappearing as employers began cutting employees and inventing the concept of restructuring the organization and laying people off after 30 years of honorable service," Bond says.

Loyalty is ultimately a two-way street, says Penelope Trunk, author of Brazen Careerist: The New Rules for Success.

The Cavaliers could be seen as disloyal to James, who will join NBA stars Dwyane Wade and Chris Bosh in Miami. "They’ve known the whole time that he doesn’t have teammates that can play up to snuff with him, and they haven’t done a good job of recruiting people to play with him," Trunk says.

"Employers have to ensure that someone has a team environment that is good for their personal growth, and employees give their best performance in exchange. This is true in all workplaces, not just the NBA."

More than anything, this was a business move for James and his brand, says veteran marketing executive Arthur Gallego.

"People are making this personal, and it’s not," Gallego says. "It’s business, and pro sports is big business. As one of the sport’s greats, everyone feels they ‘own’ him, and that’s an emotionally charged relationship."

Perhaps even more so in Cleveland.

"We can’t forget what’s happening with the economy," says Farrell, the New York professor. "It’s always been said if you’re going to be a big-league city, you have to have big-league sports.

"What does it say about Cleveland, having LeBron James choose Miami? For the fans, it’s a real sense of abandonment."