More affluent consumers are shopping at these stores, because they have enough money on hand to buy in bulk.
The Costcos of the world benefit.
More than 120 million Americans are members at wholesale clubs like Costco, Sam's Club and BJ's — and they're each potentially saving thousands of dollars a year at the register.
Sam's Club arrived in Shanghai a couple of weeks ago. It's the US retailer's fifth store in China–30,000 square meters of bulk-everything. My wi…
