This again assumes that those in the union are not wont to any disturbing intimidation of their own. The benevolence of unions by those who support them is greatly exaggerated.People from work could go home, distribute the cards, get them all signed, and then come back to work the next day unionized without the irrelevant management mucking with things.
I don't want some idiot from my work trying to come by my house to sell me the union, I don't want some idiot from my work trying to come by my house to try to do the opposite either. I don't want my work to intrude on my private life at all.