Exactly. It's not like they're coal miners or sheet metal workers.
Unions were created because employers had no opposing entity to keep wages, benefits, hours and safety in check. The NHL is exhibiting the same behaviour the owners of coal mines and factories did decades ago. Thus there is an entity to keep that behaviour in check, called the NHLPA.
Bettman and his past employers at Proskauer and Rose have realized the best mechanism for making money in professional sports is locking out players/refs. Owners of every sport except baseball have recently become their clients and voila, we have lockouts in almost every major sport. It's no secret this is business not by smart reduction of expenses or increases in revenues but by bullying employees. I can't think of a better organization to fight that than a union.