Ehh, maybe it started of as a religious thing, perhaps why Sunday was chosen specifically; but the idea of forcing everyone to have a day off is wonderful.

In the us, there's no federal law limiting the number of days people have to work. Some states have a 1 every 7 days rule. But that's not specific enough, for shift schedule work, they can set your off day to be Sunday this week, and Friday next week, and only schedule you a few hours a day so you get to work almost 2 weeks in a row with out overtime pay.

IMO, it should be (regardless of number of hours worked) on day 6 your pay is 1.5x, and day 7 is required off. At day 8 it's 2x pay, +2 days of paid vacation time (worth 8 hours or your typical shift length (which ever is larger)). It all doubles each day with out a day off. With a signed agreement between you, HR, your boss, whomever is "in charge"/owns the company and the labor board with specific documentation explaining why you have to work so many days in a row and why the job can't wait a day or someone else can't fill in. Failure to do this step results in x5 back pay for everyday worked after 6. Doubling everyday after 8.

Nah, it's definitely a worker protection ting. Sure, it has religious origins, which is why it's specifically on Sundays, but that's not why we keep it in place. It's pretty widely supported that we should have one day per week where most shops are mandated to keep closed, and nobody sees a good reason to make it any other day than Sunday, so we've kept it on Sundays.