A lot of companies already consider nights and weekends as part of the working week. Many of the companies I do business with, expect their employees to work a rostered shift program to include these times with an emphasis on weekend and night hours because that's when the works at its highest.
They also want to change the rosters regularly, obviously to suit the workload and not for the workers convenience. Then wonder why there is a large turnover of staff.
Many places with a high capital cost work 24 hours , and the shift patterns usually reflect that in their rates of pay. Hospitals have a lot of very expensive kit , such as PET, CT and MRI scanners, and I think that medics, when entering the profession , must expect to cover a 24 hour hospital, and the pay should reflect it. I have noticed that GP's, whose average pay is over £100,000 pa seem very unwilling to do home visits after hours, as they used to.
This is a decision that mainly effects England as the Scottish government do not have any plans to change doctors contracts. For me if you are having to work hours outside 8 to 5 you should be played accordingly. The problem a Lot of the time with people nowadays is the run to the doctor or A&E with some really minor issues that could wait.