Before moving to CBS, did Letterman wear suits? Â A stipulation of his contract with CBS is that, given his immense salary, he wear suits, which management deems appropriate. Â Letterman's white socks might be his subtle homage to his inherent sartorial preferences. Grayson
Actually, I don't think he ever wore suits when he was on NBC. He used to wear blue blazers or sport coats with chinos quite a lot, sometimes with sneakers. So, the white socks probably are a holdover from/homage to his high-tops with khakis era.