The world is a stratified place. Important people get into exclusive places. Everyone else has to pay shit loads of money, or watch longingly through the fence. But there's a loophole into getting into places for free, if you're so inclined. You just need to pretend to be an important person. And people who wear hi-vis are important in the sense that they fix things no one else cares about. If you see someone in hi-vis stepping through a barricade, or marching past a bouncer, you naturally assume they're headed to fix something. This makes a hi-vis vest the keys to life.