I dont have a Bible on this computer, but Christ also used an analogy of persons working in the field, the last one hired got paid as much as the first one hired, the first one complained, Jesus asked him whether he agreed to his wages at the start or not...which the man did in the parable...
So, Jesus appears to be against unions that way, too , unfair wages, and if you agreed to be paid something, stick to your word
Of course you could also view that as supporting equality of outcomes regardless of the amount of effort provided.