cause some people are paranoid, not much you can do about it

It is unsanitary. Look where your shoes have been. If you want to live in a pig sty...have at it.

It isn't a lie that wearing shoes that you've worn outside into the house brings in a lot of dirt.

When you arrive home, remove your shoes and wipe the soles off with a damp paper towel.

What do you see?

All that "stuff" is getting tracked onto the floors and into the carpet.

I live in Canada. The out of doors can be very mucky here, so, people do not wear their shoes in their houses, just try to keep them clean. At the church I go to, people take of their winter boots when they come in. It is all about cleanliness - which we know from practical experience.