Agree to is a fancy sh1t word of being forced to is more correct assumption since unions etc are not powerful enough in the USA to protect workers rights, really if i hold a gun to your head and say give me 1000 dollars and we "agree" to that transaction as well sure you arent facing the gun in the work place but really do you have a choice when unions are weak and cant protect your rights as a worker. the effect is the same as them holding a gun to you it is that level of "agreement" in place when push comes to shove.
But it sure is gullible to see the far right thinking it is a free transaction nonsense, just shows how little they actually understands of the real world out there.