New Orleans is not particularly famous for vampires as a historical fact but rather as a literary and pop culture representation. The city is often associated with vampirism in literature and popular culture, particularly in Anne Rice's "The Vampire Chronicles" series of novels, which are set in the city and feature a vampire named Lestat.
In the series, Rice's vampires are portrayed as elegant, cultured, and powerful beings, and the city of New Orleans is portrayed as a fitting backdrop for their supernatural lives. The series has a huge following and as a result, many people associate New Orleans with vampires and vampirism.
Additionally, some locals and visitors alike associate the city with vampirism because of its dark and mysterious history, with its association with death, the occult, and voodoo, as well as its cemeteries, which are above the ground, and its historic haunted houses, adding to the atmosphere of the city that can be perceived as eerie and mysterious.
It's worth noting that the vampire-related tourism in New Orleans is mostly based on fiction and it is not rooted in historical fact, although the city's culture, history, and architecture have definitely played a role in shaping the vampire representation in literature and popular culture.