It's rude to ignore your neighbors.
John, who is late to work, is pulling out of his driveway to go to work and see's his neighbor quickly approaching his car.
John wants to avoid talking to his neighbor.
John smiles and waves to his neighbor while quickly driving away.
John pretends that he doesn't see his neighbor and drives off.
John's neighbor stops to smile and waves back, happy to be acknowledged.
John's neighbor knows that he saw him and just thinks he is rude.