Even in High School kids get told to go home for wearing the wrong socks (For my sons, it was white socks with minimal logos. no stripes, no large logos, etc).
Its an obedience/rule thing (nobody is better than anybody else type thing).
Even BYU releases a 'what to wear' weekly calendar during spring/fall camps.
You wear what you are told. (The difference is, if BYU sends a kid back to the locker room to change it won't make the news 🙂 )