Fathom no more. Michigan's GOP has pushed through right-to-work legislation. While it can be argued that people who are hired by companies should not be forced to pay union dues if they do not wish to join the union or otherwise be affiliated with it (indeed, I made this same argument 20 years ago as a naive young adult getting hired into my first unionized position), it seems unjust that these same people can take advantage of the benefits of working in a bargaining unit position.
What is happening in these right-to-work states is people are choosing not to pay into the union, but still partaking in the benefits of being in a job governed by the collective bargaining agreement (CBA). Therefore, the employee gets wages and benefits as negotiated by the union, and if the employee has a concern with how management has treated him/her, that employee has the right to utilized the grievance process. Essentially, the employee gets all the benefits of union membership without the membership dues.
What's the harm? A weakened union. If the union has to spend the same amount of money and use the same amount of resources to advocate for 100% of the people under the CBA, yet they are receiving substantially less dues money to accomplish this goal, the outcomes that can be achieved are lessened and the union has less impact. Money helps create power, and by minimizing the pocketbook of the unions the companies extract some of its power. So this change is great for business, questionable for the employees that keep their union dues in their own pockets (they save now but presumably lose in the long run because a weakened union likely equates to a weakened negotiation effort for better pay and benefits), and bad for the unions that have to advocate and negotiate for these same employees with less resources.