Shoes can track germs especially if you step in dog poop or cat poop or anything else.
But actually your bare feet or socks could track in more germs into your house than shoes could ever track in.
Your feet being in the shoes can get smelly and contain more fungus, sweat and germs than the outside of your shoes.
Some people want guests to remove shoes before they enter their home while some people don't care if guests wear shoes in their home.
I'm one of the people that don't care if a person who's a guest in my house wears shoes in my house or not and they are welcome to remove the shoes if they want too but I never require them too.
You can certainly ask that your guests remove their shoes before coming into your house if you want too.
But the guests can decline in taking their shoes off and decide not to be your guests.
I like a clean house myself but I never try to force any guests to remove their shoes in my house and if they do track some dirt into the house I sweep up and vacuum the carpet which keeps it clean.
I try to sweep and vacuum daily anyway so its never a problem.
If guests in my house want to remove their shoes then they certainly can but it's up to them and I tell them they are welcome to remove their shoes if they want too but they are not required to do so.
Some people who come into my house remove their shoes and some leave their shoes on.
I have a nephew who will not remove his shoes in anybodies house but his even though I'm related to him he doesn't remove his shoes and would sleep with them on in my house unless I remove them myself.
Guests in my house are welcome to take of their shoes when they come into my house and visit but I do not ask the guests to remove their shoes and I would uncomfortable if someone asked me to remove my shoes before entering their home.
I never remove my shoes when at other peoples houses because I'm just too uncomfortable with it for some reason even though we all have feet.
Some of my guests do remove their shoes when they want too to make them feel more comfortable and at home I wear only socks and no shoes when I don't need to leave the house.
But when at other peoples houses I don't feel comfortable and feel awkward in their house without my shoes for some reason.