During the daily lunch service earlier this month, shelves in one delicatessen-style Guangzhou eatery were lined with black bread, sausages and pickled vegetables – hardly the mainstay of Chinese cuisine.But customers were coming and going at Katusha Restaurant, a 22-year-old establishment. Some discussed travel plans, others spoke about business opportunities with Chinese factories. Like the food, the customers were Russians, a nationality that has become more visible in Guangdong because of a...