Dave Zirin's books, such as What's My Name, Fool?, have brought me around to the idea that despite the perennial fan habit of complaining about mediocre overpaid players, we ought to always place these salaries within the context of how much money the owners of professional sports rake in. This is crucial when understanding collective bargaining agreements in professional sports--the most prominent players are often excoriated for greed, when sometimes the sticking point is the minimum salary for, in baseball terms, the minor leaguers and replacement players.
This issue has resurfaced with the NBA lockout. Here's Zirin:
The 21st century athlete—particularly the twenty-first-century African-American athlete—gets regularly blasted for being a weak, watered-down shadow of their more principled forebears and only caring about the money. Entire books (see Shaun Powell’s Souled Out) have been written examining their ego-driven materialism and absence of social conscience. Yet here are today’s players rejecting a deal from David Stern that would have guaranteed them their entire current contracts if they were only willing to sell out the ballers of the future.[...]
But after the players had given back $300 million in revenues, the owners wanted more. They wanted the freedom to limit the future compensation for the sport’s “middle class” role players and to be able to send anyone on their roster to the National Basketball Developmental League for up to five years while dropping their salaries to $75,000 a year. The players, without dissent, said no.
Perhaps it's a bit much to consider the highest paid professional athletes as part of the 99%. But the managements of all sorts of industries (including universities dealing with part-time professors) often try to negotiate a current raise while taking away the abilities to bargain in the future. And if the union in question can stand up to this tendency, it's commendable in any industry.