It is a mixture of things. Carpet gets dirty quicker and is harder to clean than hard floors. Hard floors are worse for your feet, ankles, knees, and cause more pain. It is healthier to walk on hard floors with shoes on, padding and carpet wasn’t much of a deal (closer to grass).

Many people are moving to house shoes, I personally don’t like them. But then again I don’t like walking on tile floors for long periods of time either. It encourages sitting/laying down more often.