The Vitamin Shoppe store on Manhattan's Upper East Side was offering plenty of deals last Wednesday. But Arthur Risk wasn't there for the sales. With list and cart in hand, he was there to do some serious shopping. The health and fitness buff was stocking up on the vitamins, supplements, protein and other nutritional products he buys on his once-a-week visits to a Vitamin Shoppe (VSI) store. Risk has been a Vitamin Shoppe customer for 10 years.