There's more than meets the eye when it comes to the membership-based wholesale retailer's dividend.Costco (COST 0.69%) shareholders have had an incredible run. Shares are up 60% over the last year and 208% over the past five. This obliterates the S&P 500's returns during both periods. Wall Street clearly loves this membership-based wholesale retailer's stock. But what is it, exactly, about Costco that investors love?We all know investors love the company's business model, which flexes its scale to provide ...