The point of contention is that in some jurisdictions the law forces every covered public sector employee to pay into the union that negotiated the agreement--whether that employee wants to or not.<p>The intention of this rule is to prevent &quot;free riders&quot;--employees who benefit from the union-negotiated agreement, but don&#x27;t contribute anything to ensure its success.<p>Voluntary unions (no forced contributions) are legal basically everywhere, as you think they would be. But they are obviously less powerful because they have fewer resources, and can&#x27;t claim that they represent all the workers.