Hubby did 33 years. If he was scheduled to work a holiday we just left it at that and celebrated on a different day. Yeah, a lot of the younger guys with no families would always take the OT pay to let someone who requested off off. There was always someone who wanted to work. Of course hubby worked for KCFD, a really large department.
I also worked for a large department. I worked on a shift that got Christmas almost every year. When I changed shifts, the new shift got into a similar rotation. But there were always overtime or trade opportunities if you were not scheduled.