Superstition

It may be hard for arachniphobes to believe that spiders ever bring good luck, but this early 20th century good luck postcard proves they do.
Further evidence comes from "The Mascot Book" by Elizabeth Villiers, published in England in 1923. According to Villiers, the spider "was popular with the Romans, who had a favourite mascot in the shape of a precious stone upon which a spider was engraved. Also they were fond of carrying little spiders of gold or silver, or any of the fortunate metals, to bring good luck in anything to do with trade."
Spiders have always meant good luck to professional weavers and spinners, for obvious reasons, but corroboration of the spider's financial symbolism is provided by a bas relief on outside of the The Bohemian Club building in San Francisco. The club was founded in the 19th century as a place for local businessmen to set aside "Dull Care" and engage in theatrical and sexual "Hi-Jinks," so the image -- of a spider and the words "weaving spiders com...