Like Harrowby, one of my sons is a firefighter. He regularly had 12 hour shifts, and like most of the firefighters he knows, they were happily accepted, because it gave them quite a lot of free time. However, he is now part of an experimental system where he does 24 hour shifts. So far, reaction from the firefighters has been mixed. Obviously it gives them a lot more free time, but 24 hours is a long time to be away from your family. Remember also that it is the law that, except in exceptional circumstances, and for particular jobs, the most that you can work in one week is 48 hours.
Incidentally the average working time per week for full time workers in the UK has come down from 38.1 hours (March to May 1992) to 37.1 hours(Oct to Dec 2017). This compares favourably with the rest of Europe.
I suggest that the rights of workers have made huge strides, especially when you compare the average worker in 1870 working 66 hours a week to less than 40 today, and that is not including the huge change in rights and benefits the average worker enjoys. That is not to say that working conditions and benefits shouldn't be improved, but it is a world away from the idea that we are encouraged to 'work ourselves to death' as SweetPea seems to think.