Walking into Aji Ichiban, a bulk snack emporium in Rockville, Md., is a little bit like entering Willy Wonka's candy factory — if Willy Wonka were Asian. Visitors are greeted by a dazzling array of foil-wrapped chocolates, fruit-flavored marshmallows, European nougat confections, and a selection of gelatinous goodies that put Haribo gummy bears to shame. But candy is only the half of it. Aji Ichiban is a Hong Kong chain, and their U.S. stores sell......