I guess it's because patients are not prisoners, hospitals can't really control their behavior and to be fair: they shouldn't have to. A sane person would simply comply with the doctor's recommendations. It would make sense to talk to the enablers, make it clear to them that they too need to change what they are doing. They are probably doing this already. Of course it won't work in many cases, but the same problem applies once they leave the hospital so there is no much else medical professionals can do.