NEW YORK -- Marvin Weiner, who developed magazine racks for the checkout aisles of supermarkets, died here last month after suffering from cancer. He was 78. Weiner launched Brand Manufacturing in 1956, and developed display racks for L'eggs pantyhose before working with the Time magazine group on its supermarket display racks and with individual supermarket chains on their checkout-aisle magazine racks, according to Robert Aders, a former executive at Kroger, Cincinnati, and past president of Food Marketing Institute, Washington. Weiner was active in both FMI and the General Merchandise Distributors Council, Colorado Springs, Colo., and was a frequent contributor to local charities, Aders said.