Blame it on #evolution. When humans began walking upright, it had many flip side too. The anal region is subjected to increased pressure unlike#monkeys and other animals that walk on four feet.So the increase in pressure points is a fundamental problem that has the potential to cause hemorrhoid or piles. If we add this natural disadvantage to the unnatural position in which we pass our stool by adopting western toilets , readymade foods without fibre and sedentary life, the occurrence of piles increases phenomenally in humans.
Piles is a penalty we pay for our erect posture.