Why do some people wear socks when wearing flip flops or sandals?

Socks and sandals is a strange habit. Here in the uk it happens a lot. I don’t see women doing it ,only men.
Then again I think it’s silly in summer for men to wear trainers with shorts . Sadly these always seem to be worn with white socks and looks dreadful, many young men seem to do this
Surely sandals without socks are much comfier when it’s hot.
I’ve got proper hiking sandals I wear when out all summer.