This is turning into a record sales summer for the book business. “The impressive sales totals partly reflect the growing power of big discounters like Wal-Mart and price clubs like Costco. In a sea change for the publishing business, those outlets accounted for as much as half of the early sales of the three books and can claim as large a share as traditional bookstores and online outlets, according to the publishers and an analysis of sales of figures. The power of the price clubs and discounters to move huge numbers of certain books is giddily unnerving for book publishers. The good news is that millions of consumers bought books last month. The bad news is that a lot of them skipped a trip to the bookstore, where they may have bought even more books. For a growing number of consumers, however, the nontraditional outlets simply mean cheaper books.”