The ability to squat is also important for another reason: health. Contrary to Western ideas about toilet design, human beings were not meant to evacuate waste in the sitting position. The best toileting posture is squatting -- the posture used by most Asians, Africans, people living in the Middle East and other regions of the world.
"The ideal posture for (elimination) is the squatting position, with the thighs flexed upon the abdomen. In this way the capacity of the abdominal cavity is greatly diminished and intra-abdominal pressure is increased, thus encouraging expulsion."
However, as a result of a confluence of several events/factors in history -- the mistaken idea that sitting is more dignified and 'civilized' than squatting, the invention of sitting toilets, the availability of sewers and indoor plumbing in the mid 19th century (during the Industrial Revolution) -- one third of humanity has ended up abandoning the squatting posture.
Today, with few exceptions (eg: France), it is virtually impossible for a visitor to find squat toilets in Western countries.
The habit of sitting for defecation has given rise to a strange defining characteristic of Western peoples: one in three adults (according to one study) is incapable of holding the squatting position for more than thirty seconds.