Daggers come out of their eyeballs, steam comes out of their ears, they levitate 6 inches out off the ground, and growl “Corporations are NOT PEOPLE!!!!!!!!"”
Then neither are Unions...
No, they aren't. However, they are legal PERSONS. And it's a good thing they are. Otherwise it would be impossible to do business with them. If corporations weren't legal persons, able to make contracts, and to be sued for breaking them, you would find yourself dealing with one of the workers, who had no authority to bind the corporation itself. What happens when that person moves, dies, or retires? Only because that person was acting as an agent of the corporation, can the corporation be held bound by the contract.