The more and more I think about it, why should the players, who are employees of the owners, get more than 50%? It was 50% in the early 1990's and has been creeping up with every new CBA since.
Actually I don't know if this changes your opinion at all, but I don't believe the players are actually employees, I believe they're considered independent contractors. Just like I (as well as the IRS) don't consider the band/singer/rapper an employee of their record label. Same thing with athletes.
As independent contractors they have the right to choose the terms to which they will work. If I hire a plumber (usually also an independent contractor), they have the right to quote me a price they'll work for, and I have the right to negotiate that price more to my liking.
I don't know about you, but it changes my expectations of things. I do think the players have the right to demand a larger percentage. But maybe it's just semantics (cuz I also think any employee has the right to decide the terms to which they'll work).
EDIT - according to the state of California I'm wrong. Athletes for team sports (baseball, basketball, football, etc.) are considered employees, for individual sports (gold, tennis, boxing, etc.) they're considered independent contractors.
http://www.edd.ca.gov/uibdg/Total_and_Partial_Unemployment_TPU_4154.htm