In many countries like Germany, Switzerland, in Skandinavian countries etc. it is common use to take off the shoes when entering someone’s home(*). The custom of removing shoes is widespread also in Eastern countries like Japan, Korea and Turkey.
In these countries it is considered a major faux pas to walk through a house with shoes on. In some schools in Sweden, children are even required to remove their shoes.
The writer seems a little reserved about making shoes off a rule for guests, but otherwise has some good thoughts on the subject.