It's rude to hover behind someone.
Bobby is waiting in line at the store and there are people in front and behind him.
Bobby wants to pay for his groceries and leave the store.
Bobby keeps his social distance from the people in line, avoiding the sneeze of a person ahead of him and then pays for his groceries.
Bobby is waiting in line very close to the person in front of him and ends up getting some droplets on his arm when this person sneezes.
Bobby gets food to eat and is tested negative for covid-19 at his next DR's appointment.
Bobby finds out that he got coronavirus from the person who sneezed on him.