you track feces all over the house whether you take your shoes off or not. Do you touch your shoes with your hands when you take them on and off? Yay, feces on your hands. I will always take my shoes off in someone else's house if that's the custom. It does bring in dirt. But people need to get off this stupid fucking "OMG E. coli" thing. The number of fuckwits writing such articles makes me sick.