In many places (Europe, generally?), vacation days are earned. At least in the Netherlands if you were absent for weeks due to illness (for which there is no fixed pool of days), and decided not to take any vacation days, you'd either have some of your vacation days rolled over to the next year or they'd be paid out to you with salary and taxed.
It's not a luxury in the slightest. You'd have earned them just as you earned your wages.
But parental leave is considered as work, so if you come back after your parental leave, you have your full amount.
There's no distinction, at least not with the statutory holidays. You earn them as you earn your wages and there is no adjustment for illness.
Why wouldn't you?
If you missed weeks of work from an illness, those weeks aren't time where you could see family, see the world, relax, and be human. They don't satisfy the same long-term needs as fully-disconnected vacation time satisfies.
It does point out that they'd need to enforce a reasonable minimum number of sick days if they're forcing them to be separate from PTO.
Places I had worked including my current employer, vacation days need to be scheduled at least a week+ in advance. As a person who gets sick a lot I almost always end up having to take unpaid days off when I’m sick because I blew though my 3-5 sick days.
Places with PTO I can take my entire pool off as sick time. Never took an unpaid day at a PTO business.
Right now. I have 400+ hours of banked vacation time, but I have used all of my sick days for the year. If I get sick I have to take it unpaid or work. It doesn’t make any sense.
Honestly I think they should outlaw having them separate.