When you have open sores on your feet and you walk around barefoot on the ground or in places you do not know how clean they are then it's possible to get sick and catch some diseases from walking barefoot.
But just walking around barefoot should not cause any diseases and it's actually better for your feet to not wear shoes when you do not need too.
I love to walk around my yard barefoot and when I go to the beach I love to take off my shoes and walk around barefoot in the sand.
It feels so good to walk around barefoot like it was meant for us to do.
Allowing your feet to air out by walking barefoot keeps your feet and skin healthy and makes your feet feel much better.