For Cindy Wang, the newly opened “community store” near her home in Guangzhou has been a godsend: the small outlet is cheaper than a traditional supermarket, but offers a bigger range of groceries than convenience stores like 7-Eleven.The 20-something now often stops off at the shop after work to pick up a few items. On an early September evening, she has bagged a bottle of milk for just 7 yuan (US$1), a 2.5 yuan beer and some mangoes priced at 10 yuan per kilogram.“It’s convenient and...