You're on your own, unless you're among the educated elite:
I tend to think it's easier to not see the lack of mandatory paid vacation and holiday as much of a problem if you're a highly educated, white collar worker, and even easier if you're a stay-at-home, freelance writer. It will simply never be true for you that the minimum is your reality.
But that doesn't mean it's not true for others. According to the CEPR study (pdf), about a quarter of workers don't get any paid vacation or holidays. If you make less than $15 an hour, that number jumps to 31%. If you do get paid vacation, on average, you get 12 days of it a year. That's less than the statutory minimum in every advanced country save Japan and Canada, and I'd bet the average in both countries well outpaces the average here.
And it's not just vacation days. Nearly half of all private sector workers get no paid sick days. In the bottom quarter of US workers, 80% are deprived -- and this is exactly the group that can't afford to take an unpaid sick day. And so far as family values go, only one in three workers has paid sick days they can use to care for ill children.