What happens every time a union tries to put a collar around the neck of the largest employer in North America? One of two things: The union vote fails or the vote passes and Walmart shuts the doors on that store. Why, you may ask? Because Walmart knows that setting up a third party as a defacto staffing agency and giving control over your company to a leadership team concerned only with continually increasing union dues is bad for business.
Question: Have you ever seen any butchers in Walmart? Several years ago you might have until the butchers voted to unionize whereupon management decided to sell only precut meat in the stores. So what do you do if you are a union and you can't crack the Walmart nut through secret ballot elections? You get rid of the secret ballot via card check.
As usual, Red Planet Cartoons has a picture that says a thousand words: