From what I see with my mother in law, the staffing (direct contact like nurses and cleaning), admin and security, cooking, pharmacist, and general maintenance are a pretty big cost. Add in insurance costs, both the employees benefits kind, the liability for the facility, and liability for the staff, and i can see why the cost is what it is.
Some of it is area-specific. Full time care like my MIL needs is cheaper in a small town than in a big city, assuming you can find one on a small town. I imagine it varies by state, as some set insurance requirements at different levels than others.
Agree this kind of care is expensive. I'm not sure how to simultaneously lower cost and add staff.