The best and worst and most unoriginal and lazy excuse made up by adolescents to do stupid things. It has been passed down from the beginning of time. Used on parents and other friends and acquittances who live above the influence to make them stop bothering you about the stupid thing you're doing.
Half the time not "everyone" does it, its usually just a handful of people who seem cool at the time, but probably will end up being prostitutes or drug dealers or politicians, or all at the same time.
Mom- why do you wear your pants so low? It's gross and makes you seem like a douche.