Unions work when there is a shortage in skilled potential employees and a long learning ramp-up period. Unions work not very well when there is a glut of skilled people, or there are enough people with lower skills willing to take a lower pay rate (or where that lower pay rate is considered well-paid). There is no shortage of people who want to work in the game industry. There is a sorta shortage in people who know game engines in and out, and people who don't need to refer constantly to API references... people who put in 35-40 hour work weeks competing with people willing to put in 45 hour work weeks are generally at a disadvantage.