The easy savings were made years ago. Now you have to get really clever.
Many PVF players today operate out of modernized facilities, utilizing wondrous material handling equipment and wireless bar code scanners to keep track of the flow of goods. These things removed inefficiencies in large chunks. Costs today get extracted at a pennies per line item pace, or through vendor managed inventory (VMI) or integrated supply arrangements that essentially eliminate competition but carry a staggering premium in customer service.