The struggle to control prices of digital content sold online continues, with producers and distributors battling over prices for downloads of books and music. In the latest skirmish, Amazon removed Macmillan books from its website after the company protested that online retail was using monopoly power to force publishers to accept prices no higher than $9.99. Macmillan and other publishers have now signed distribution deals with Apple that allows them to price downloads at $12.99 and $14.99. Producers, of course, want higher prices because they produce higher revenue and better profits. The struggle to control prices is not unique to the online environment. In the offline world, producers of books, magazines, CDs, and DVDs have long struggled to gain limited shelf space because there is a large oversupply of products and retailers’ have selection preferences for popular, rapidly selling products. Large national and retailers have also used their bargaining power to push wholesale and...