Why do tennis players wear 2 pairs of socks?
Tennis players wear 2 pairs of socks for the extra cushioning, softness and comfort over the course of not just a tennis match but a whole tournament.
Tennis socks guide — thick tennis socks RSS
Should I wear thick socks when playing tennis?
Many professional tennis players wear two pairs of tennis socks during their matches for added thickness. So, yes, tennis players generally prefer thicker socks when they play.