If they are so great and such a wonderful benefit then they should be overrun with people voluntarily sending them dues and should never have mandatory deductions from people who don't want to participate.

Those in favor of unions and all their wonderful benefits should be the ones funding them, although public sector unions should be banned outright. Even the socialist FDR was opposed to public sector unions.

Kinda like the 'Affordable' Care Act that is so wonderful and affordable it's mandatory and if you can't afford it you get fined.