My theory as to why Egyptians seemed to be so preoccupied with continuity and permanence is that the Egyptians had many gods and the fact that they thought of their kings as being a god who is temporarily here on earth but when the king dies they believe him to go to an afterlife. This is demonstrated through out almost all the dynasties art works. As well as in their writings they wrote in hieroglyphs.
The Egyptians believed that by making the pyramids as these enormas burial places helped them to travel to wherever they went when they died, and went to join the other gods in the sky. This however strange it may seem is not far from the religions taught in todays time.
The Egyptians also later in time believed the pyramid to be the home for their spirt when they died hence this is why they started putting objects and people in the pyramids with their king the servants would serve the king in the after life.