Public servants -- meaning government employees -- don’t work for greedy miscreants exploiting them for personal profit. They work for democratically elected officials representing the will of the people. This is just one reason why there is no legitimate role for government unions, and there should be no collective bargaining rights for public servants.
Since public servants work for the people, their wages, benefits, and working conditions are set in accordance with the will of the people, as determined by the democratic process. This is why it is not legitimate to ask the people to compromise with public servants in collective bargaining. And this is why the pay, benefits, and working conditions for federal workers are set by acts of Congress, not through collective bargaining.
If public servants do not like the pay, benefits, and working conditions offered to them by the people as determined through the democratic process, nothing requires them to be public servants. This is why public servants are not slaves without collective bargaining, as soon-to-be-unemployed collective bargaining agents have suggested.