The problems that J.C.Penney, Macy’s and Sears have had in recent years has been blamed largely on the rise of online shopping alternatives — primarily Amazon.com. But the issues department stores have go beyond Amazon to include competition from off-price chains such as Marshalls and T.J. Maxx as well as specialty retailers including Sephora and Ulta. Making things worse are decisions by vendors such as Michael Kors and Ralph Lauren to cut back on lines they make available to department stores.