It all began when vagrant kids who lived near a bus or
truck terminal notice that some drivers customized their vehicle
horn to play popular tunes or just sound amusing. With no other source of entertainment like TV, and playing games gets old, they use those custom
horn sound as their source of entertainment.
What began as a small group of children now has grown as a fad to even bigger numbers of children, all waiting in a row facing passing trucks and buses. Sometime with a phone to record video in hand, they shout the word or carries a simple cardboard sign scribbled with "Om (lit. uncle, also usually used as informal term for older/middle aged male) telolet (onomatopoeia of
horn/klaxon sound, like honk
honk) om.", basically meaning "Sir,
honk please sir"