These sorts of abuse work on the implicit threat of retaliation if you don't agree to the abuse. A union provides a roughly equivalent counter-threat, which act

These sorts of abuse work on the implicit threat of retaliation if you don't agree to the abuse. A union provides a roughly equivalent counter-threat, which acts as an incentive to not be so abusive. Would we love to not operate on threats and counter-threats? Sure, but that would require the mutual consent of both parties, and the ones in power have rejected that outright.