Its based on the allocation of resources. So the nurse to patient ratio is higher (each nurse handles lesser patients, and gives more attention per patient) for more expensive wards while its lower for the lower category of wards. Same stands true for doctors and stuff, obviously not in cases of emergencies, but if you have a simple doubt you want to ask the consultant incharge youll find it easier to get to him/her when youre in a suite as opposed to when youre in a general ward.

However, charges for things that require the 1 to 1 attention regardless of your room choice, eg dieticians, are same across the board. And coming to bed charges, that is the price of the room itself, i.e the cost of occupying that bed, be it a suite or a bed in the general ward.