With rare exceptions, my industry, electronics, has never been unionized. It probably would be more accurate to say that its compensation packages, through many decades, were designed to keep workers too satisfied to want to unionize (because union work rules are designed to be inefficient and inflexible). And yet I'm middle class, union-free. How'd that happen?
My Dad was a land-owning farmer, as was his Dad. Again, both middle class, with no union in their lives. How'd that happen?
My maternal grandfather was a teamster, a delivery route driver delivering fuel and lubricants to farmers. Just short of qualifying for his pension he had a heart attack, and his employer canned him, basically to save the pension $$. His union didn't lift a finger for him and my Mom had to support him and her mother (mental problems) in his declining years (which happened to be during the Great Depression).
There are reasons I'm the antithesis of a union-worshiper and these are just from my family history.