My mother was told to let me run around in bare feet when I was a baby - I think it was supposed to be better for your feet. As a teenager/ young adult I wore high-heels all day and Scholl sandals at home. In the summer I wore open-toed sandals and, yes, liked to paint my toenails.
As a primary school teacher I spent most of my day on my feet and they were often trodden on by my pupils. My big toe nails were both damaged by children rocking on their chairs and then bringing the chair leg down on my foot - OUCH!
In my 50s I developed what they thought was plantar fasciitis, but turned out I needed a calcaneal osteotomy - foot operation where they cut the bones to re-align them and insert metal rods (under general anaesthetic). The whole procedure and recovery took two years, so now I look after my feet. I wear flat shoes with inbuilt orthotic soles, have regular pedicures and have my toe nails painted - usually pillarbox red!