Nosy drivers who turn their heads to look at accidents thus causing severe traffic jams on many roadways.
While rubberneckers looked at a bunny rabbit, they caused a traffic jam.
People that stick their nose into other peoples business.. always wanting to know whats goin on or what the other person has.
Perfect Example for Rubberneckers is from the movie Secret Window.
Ted: Maybe I should take a walk around the block.
Amy: Yes, that'd be good.
Mort: Aw heck, Ted, live a little - make it two. Rubbernecker.