People who go without hats have never worked out in a bean field or cattle farm all day long. Where I have lived, going without a hat will get you your brain baked.
Word.
I'm in the rain gutter business, which means I spend my days outside in the sun on ladders and rooftops. At the very least, during the warm months, I wear a bandana covering my head, but when the Texas sun really bears down, I've got one of my straw cowboy hats on.
I couldn't work in the sun without one.