Describe symbolism in Violets Are Blue by James Patterson

The murders of the two celebrities symbolizes the degree to which the killers fit into society. They refuse to feed on street people and other victims that may go
unnoticed. Instead, they acquire some of the best seats in the house. They appear so normal, in fact, that the celebrities readily invite them to their room. These things make the killer far more formidable, as the reader begins to feel that they could represent a type of person that one would run into in the street.