Most major sports in the U.S. have players union. Football, baseball, basketball, and hockey players all leverage the power of collective bargaining to fight the power and money of the team owners. Boxers don't have a union, but they do have the Muhammad Ali Act.
Wikipedia describes the act:
In general, the act restricts the types of contract that a boxer may be required to sign in order to box at an event. The boxer cannot, for example, be required to give away future promotional rights as a requirement of competing in a fight that is a mandatory bout under the rules of a sanctioning organization. The act also requires sanctioning bodies to reveal to state commissions various information about matches that are held, fees charged to boxers for the sanctioning body to sanction a match, as well as any payment or compensation received from the body for affiliating itself with the promoter. It also requires promoters to disclose a large amount of the financial information about bouts to the state commissions, as well as to the boxers they promote.
You'll notice the part in italics is something that MMA promoters do as a matter of course. We call it the "champion's clause".
Herschel Walker brings his considerable experience as a pro football player in the NFL and the USFL and a dues paying member of a players union to MMA. He talked to MMA Junkie about the need for a fighters union:
"I think the fighters in the sport are just now starting to make good money," Walker said. "The promoters are making good money, and sooner or later the fighters should start making good money. Some of them make OK money but not great money. But the way the contracts are written for the UFC, sooner or later there needs to be a union. I think a union should come in."
"I don't know the dollars, and I'm not going to get into the pockets of the UFC, but if you start looking at the amount of money they make, which I don't know the exact amount, but look at the amount of money they make, if someone audited their books - you can't tell me in an individual sport you can't have a union and have a guy that has four or five professional fights and let them be part of the union," Walker said. "Once you become part of the union, you can get insurance. You can get certain benefits that aren't there right now. I don't know why that can't happen."
Lorenzo Fertitta addressed the topic at the 2010 UFC expo. Fertitta is playing a skillful, subtle game here. A fighter's union (or even worse the application of the Ali Act to MMA) would be a major headache for the UFC, but Feritta takes the angle that it's simply out of his hands:
"We have no role," Fertitta said. "So we're not in a position to say we support it, or we're against it. That's entirely up to [the fighters]."
"One of the things that's a little bit different is that fighting in general - I know a lot of people have talked about the same issue (with) boxing - fighting seems to be such a individual sport," he said. "And guys have different needs and different motivations, and what's good for a guy like Chuck Liddell is maybe not good for a kid like Paul Kelly coming up.
"They have different needs and are (at) different times in their careers, so I'm not sure if it works or not."
That's pretty singularly disingenuous for a guy whose casino business is constantly at war with their union workers. In fact, it's been speculated that the unions are opposing MMA legalization in New York state as a way to punish the Fertittas for their labor practices.
"Unless you can get the top athletes and you're not going to do that. I mean the fighters, they're all whores, they just fight for the biggest purse and it's going to be tough unless you could somehow get all the fighters to agree to something like that and you know there's always somebody going to come up underneath who's not willing to do it. Like I said, it doesn't matter who the best guys are, it only matters what the announcers are telling you who the best guys are and the fans are going to believe it."
"There's enough support (for a union) but these guys, outside of the cage or outside of the ropes, these guys are cowards, you know they would not dare stand up to the powers-that-be."
"You only have a finite amount (of years) that you can compete and you want to make as much money as you can in that time and you don't want to mess around with the politics of the sport."
There is the MMAFA which is attempting to start a fighter's association but I'm not sure that they are building any momentum.