Sarcasm is a language of a particular subculture. Not everybody speaks the language of sarcasm. Sarcasm is a game of opposites. Many people enjoy playing that game and even consider it an art. A toddler might draw on the wall with his own poop and consider it art. Is sarcasm an art? Is wall poop an art? That all depends on whether someone has to clean up the mess afterwards or will let it sit there and slide down the wall.