Why did the citizen lie about his destination to the innkeeper?

The citizen lied in order to gain entrance to the inn..... just for a night. He was infected by the plague and had escaped the incarceration of his own home. As a result, he died in the inn, infecting the inn and the area surrounding it.

I remember one citizen who, having thus broken out of his house in Aldersgate Street or thereabout, went along the road to Islington; he attempted to have gone in at the Angel Inn, and after that the White Horse, two inns known still by the same signs, but was refused; after which he came to the Pied Bull, an inn also still continuing the same sign. He asked them for lodging for one night only, pretending to be going into Lincolnshire, and assuring them of his being very sound and free from the infection, which also at that time had not reached much that way.