None of them, of course, will ever take the place of La Boqueria, the beloved central food market in this Catalan capital on Spain’s Mediterranean coast. But that cornucopia just off La Rambla is also a tourist magnet. And with the fruit vendors at its entrance hawking hyper-colored juices to the fanny-packed hordes and backpackers milling around and eating from plastic takeout containers, it can sometimes feel as if tourists outnumber locals.