Every private sector company i worked for paid shift differential for unpopular shifts (usually nights/weekends).
PTO for someone in most management (salaried) positions is not worth much. You essentially have to squeeze the work in before you leave and/or get it done after you come back. The true advantage of hourly positions, imo, is that ability to let work stay at work. If you take time off, someone else will pick up the slack.
This is part of the reason why most managers, all the way up to CEO make so much more money. Even when they are off, part of their brain is at work. They also have far less job security than most hourly workers. I did it because I liked the work and I was good at it.
I have always fell into a weird category, not really "field", not "management", not "office". Superintendent years ago, that has supervisory rolls, but is also field, and also some office.
Inspection, when I was with the county, that was 100% in the field, only office I saw was dropping reports/timesheets off on Friday, but they still didnt generally categorize us as "field". Now, current role, they say, it's 80% field, 20% "office", but that's really car office. Even when I temporarily filled a higher position, it was targeted as 80% office, and 20% field work.
But, I agree 100% with the "it's too much work to take a day off" part. You work twice as hard for 2 or 3 days to get stuff ready to take a couple days off; then 2 or 3 days un "F'ing" everything when you get back. It's easier to just go to work. I avoid taking off Friday, cause I still have to do my time sheet, approve others time sheets, do status reports, ect, regardless of being "off" or not. Sure, it's not that much time, but it's the fact that it has to get done by 9am regardless of PTO/vacation or whatever.
On the shift diff; we get nothing extra for nights/weekends/hurricanes, ect, unless you go over 40 hours. Sucks when you do a Sunday night, Monday day, Monday Night, and Tuesday day run; and then they send you home Wednesday/Thursday/Friday.
All that, is just complaining; could be paid by the mile drive, linear foot of pipe installed, or commission. I know a lot of guys that get either a per-diem plus footage, or just straight footage pay. You might make $600 in a day, then $20 the next. Weather really screws them; but at the same time; it screws the owner as well. Probably a better way is min wage, plus production. And, Yes, different roles do normally get a different production price. A driller might get $2/foot, and a laborer might get $0.50/foot.
I should add; only people I know that get a shift diff are medical. Wife gets like $4/hour for nights; and maybe $2.50/hour for weekends; but if I'm not mistaken, that Night pay is only for the portion of a shift from 11p-7a; so not even the full shift gets the added diff.