Costco had a decent fiscal 2016, with comparable-store sales up 4% globally and 3% in the United States when the impact of falling gasoline prices is factored out. Costco could be a digital powerhouse greatly increasing overall sales by giving its members reasons to not go to Amazon or other online retailers. Costco (NASDAQ: COST) continues to squander an opportunity by operating as if the internet has not become a major factor in retail.