They're references to old fashioned sartorial etiquette: https://sartorialnotes.com/2016/09/02/never-wear-brown-in-town/#:~:text=%E2%80%9CNever%20wear%20brown%2

They're references to old fashioned sartorial etiquette: https://sartorialnotes.com/2016/09/02/never-wear-brown-in-town/#:~:text=%E2%80%9CNever%20wear%20brown%20in%20town,escape%20the%20opprobrium%20of%20colleagues.&text=%E2%80%9CIf%20you%20work%20in%20insurance,black%20Church's%20or%20Cheaneys.%E2%80%9D%E2%80%9D https://sartorialnotes.com/2016/09/02/never-wear-brown-in-to... and https://learningenglish.voanews.com/a/why-americans-don-t-wear-white-after-labor-day/5060464.html https://learningenglish.voanews.com/a/why-americans-don-t-we...