That's a good observation, and hold true in Canada to an extent too. In the US, union participation is 10% [1] while in Canada it's about 30% [2]. In the EU it's just short of 60% [3]. Amazing how each doubling or tripling of labor union participation rates creates monumental changes in the way employees are treated: minimum 35 days of PTO in Europe, guaranteed child care, mat/pat leave. It's almost like collective bargaining works.
US PTO: 0 days (!!), CA PTO: 16-30 days, EU PTO: Up to 36 days.
It was only 50 years ago that the Republicans were the party of labor unions [4]. How times changed.