This is partly due to the training that NPs receive and research showing that patient and family centered care allows for better patient outcomes. I also believe that as NPs become associated with better patient outcomes, other physicians will begin to adopt these same methods and techniques proven to produce better patient outcomes.
References
Sangster-Gormley, E., Frisch, N., & Schreiber, R. (2013). Articulating new outcomes of nurse practitioner practice. Journal Of The American Association Of Nurse Practitioners, 25(12), 653-658.