Unions are there to negotiate not dictate. Labor contracts are reached through negotiation. As a negotiator --union or management--you never come away with 100% of your initial demands. Unions don't generally have enough clout to get everything. As it foolhardy for a union to kill the golden goose, it is also incumbent on management not to give away the store. The function of unions is to negotiate contracts where their members can make a decent living so that their basic needs can be met. Unions also are charged with negotiating work rules that that protect the health and safety of their members. Unions also serve as a conduit in resolving disputes in the work place.
After all, an employee is not a wage slave. He/She is a person that is deserving of dignity and respect. If that recognition existed to a greater extent in the work place then there would not be a need for a union. But in a world where CEO are paid 400X the basic workers pay, I can't understand the all the beef about unions.