do all gardeners use nail brushes?

I often wonder how gardeners can just dig their bare hands into the soil and be okay with always having dirt under their fingernails. The soil is full of microbes, so isn't it really unhygienic to have dirty fingernails when you're back inside after the gardening session, when you're cooking in the kitchen or doing other things? 

I discovered that nail brushes are a thing, and they do a decent job at cleaning the dirt out, but are they commonly used? Je ne sais pas. 

addendum. Apparently, if you scrape your nails in a bar of soap before the gardening session, there'll be less space for the dirt to get in.