We are not allowed to do shifts any longer than 12 hours, except in an AOG situation when we can only work a max of 16 and then have an 11 hour break, we can not work more than 7 days without a rest day.
And yes I have walked away from an AOG at the 16 hour point and come back the next day, you have to have the courage of your convictions and an employer that will support you helps.
So you see some are more regulated than others, the problem is with employers who have no concept of human factors or health and safety.
Therefore do not tar everyone with the same brush. Some employers do actually care.