I read an interview with one of the union leaders - forget which one- that was really interesting to me, because you don't get the other side of this in the msm, and certainly not here where damo the union hater always has some story of some evil union person who threatened to torture some poor guy's children in front of him and laugh while they screamed, if he dared to vote for the union.
According to this guy, it's not the secret ballot that they are against, but rather, all of the tactics used by companies in the run-up to that ballot. all very heavy handed, including a lot of pressure from the person who can deny you a promotion, raise, etc, and in private, one on one. that was just part of it.
and having done some work several years ago against walmarts anti-union tactics, these things definitely happen, so it made sense.