Nothing scares Union leaders more than the threat to not collect Union Dues from paychecks for them. They know that if they had to do the collecting on their own it would be a financial catastrophy.
Not getting the dues by any means scares them. Back in the '60s a buddy of mine worked in a small unionized foundry where the owner was screwing them left and right - and the union did nothing. The union members all withheld their next payment of dues in protest.
The next day a suit, accompanied by two human mountains called Mr. Lefty and Mr. Fingers showed up to "straighten things out". The rebellious members told the suit that they weren't going to pay any more dues until the union went to bat for them. Mr. Lefty says, "If youse guys don't pay up, there's gonna be an 'industrial accident' here". All the guys grabbed some BIG mallets (used to knock open the molds) and replied they wouldn't be the only ones who had an "accident".
The suit steps in between the guys and says everything will be taken care of now, so just go back to work - and pay your dues. Nothing ever changed and my buddy quit in disgust.
Maybe a video documentary of all the lavish perks the union bosses will lose if the dues aren’t paid would help to convince all of us doubters how wrong we are not to support the unions?
Collecting the dues directly from the paychecks saves the unions a lot of money by not having to hire people to break thumbs to collect.