There are good union and there are bad ones. Once it becomes about money and power, not about taking care of your people, or just juicing the system then it becomes a bad union. I don't know enough about the Player's Union to make a call on it. Unions can and will split sometimes once management gets corrupt and greedy.
If anyone is interested in Unions I recommend,
Labor's Untold Story, by Richard O. Boyer & Herbert M. Morais.
More About Labor's Untold Story