Those who think that residents cost hospitals money are idiots. Pure idiots. It's amazing that any of these idiots managed to make it through medical school if they could not deduce a simple logical comparison.
Residents do medical work that needs to be done, and work for slave wages. 50k/yr or thereabouts
NPs, PAs etc do medical work that needs to be done, but work for a fair salary, and demand fair hours and extra pay for longer hours. 100k/yr or thereabouts
Attending physicians do medical work that needs to be done, but work for a very high but fair salary. 300k/yr or thereabouts
Hospitals save lots of money with residents.