Yes, that they're mad that you don't understand what a union is.
I'm not gonna make any claims that unions are perfect, but a union is just a way for a collection of workers to have more leverage for bargaining rights. The most prosperous times for workers in the last century have been during times of heavy unionization.
Reagan busted the unions, and with them, he busted middle-class prosperity. As is often said, we owe weekends and the end of child labour to unions.
As a long-term worker in the industry, I'd love a union, particularly if I were to go back to work at one of the huge game companies like EA (ugh) or Rockstar or Blizzard.