NEW YORK (AP) — Allison Hill, CEO of the American Booksellers Association, is used to strangers expressing sympathy when they learn what she does for a living. “It’s all so funny,” she says. “When I tell them I run the trade association for independent stores, they’ll say, ‘It’s just so sad that they’re disappearing.’ I don’t think they’re really keeping track, or they just know about a store that closed or heard about one closing.”The decline of physical bookstores remains so embedded in popular culture that the man dating Anne Hathaway’s character in “ The Devil Wears Prada 2 ” laments that bookstores are “getting downsized and consolidated.” But the decline actually ended years ago, and the latest numbers from the American Booksellers Association show independent stores expanding at a pace not seen this century. Membership in the ABA grew by more than 500 over the past year, to a total of 3,417 (at 3,783 locations), nearly triple what it was a decade ago and the highest level since the late 1990s. The surge included stores of various kinds — general interest shops like Hey Books! in San Diego; mobile stores like the Wandering Quills Bookshop in Westerville, Ohio; pop-up stores like Banyan Books in St. Petersburg, Florida. Many of the new members reflect the current boom in romance, fantasy and their hybrid, romantasy, whether the Spicy Librarian in Denver or the Flutter Romance Bookstore in Austin, Texas: “Where butterflies begin. And every story ends in happily-ever-after,” according to its web site.