I once was on a tour of a non union maintenance shop, in an area where most similar shops were union. One of the people on the tour asked the manager about this.
His answer- 'Every shop around here that's gone union, has deserved it. I pay my guys above average, I don't flip out when they take time off, and we have decent health insurance. My workers are happy- when the union comes calling it's the workers who tell them to get lost.'
If WotC is going union, they probably deserve it.