You apply for medical training 6 to 7 years before your first pay check, so its not entirely fair to say they new what they were getting themselves in for.
During my time as a JD we saw pension reform, imposed contracts, year on year of pay freeze or sub inflation rises. None of this will have been known to me at the time of applying, we just rolled over and took it apart from one brief period of tepid IA.
It's not an easy situation being beholden to a single employer and seeing your salary being held down for the good of the public finances.