Why Americans and British have carpets for flooring?

Seriously why? I have been watching movies and I have this random question. I even noticed in movies people walk with their shoes on carpet floors but I hope this doesn't exist in real life. It looks unhygienic and hard to clean (probably needs expensive equipment) and I suppose it needs to be replaced often. It looks like a nightmare if you have pets. I like walking barefoot in my home and it feels gross. I still choose big carpets for my wood and tile floors but I can easily clean them and I like using jute carpets in the summer.