Federal employees presumably get the ones designated for them as part of their employment but that doesn't mean they get them. For example, even though I worked for USPS whose workforce was behind the shift of a February holiday to January (MLK day) I never got off on that day ~ never. Of course you got paid for it though, didn't you? And you were paid extra or comped with a different day off.
I will work MLK as a standard work day. No time off, no comp, no premium time.
There was no comp time. There was no alternative day off. The work didn't let up just because somebody had a holiday, but this was for extra work.
We had a couple of folks around with a UNION attitude, but they were the exception. You want a professional job with exacting requirements you do that job. If you want to tamp asphalt into a chuckhole then you go get that other job.