It’s a midsummer day and the sun is high in the sky, but the cavernous bar on the green, hilly 68-acre Rios-Lovell Winery & Event Venue stands empty.Although Rios-Lovell and around 50 neighbouring wineries in the San Francisco suburb of Livermore typically do not expect many clients on weekdays, they also know that Generation Z and Millennials are not drinking as much as their elders.However, the 35-year-old Rios-Lovell winery ships a couple of containers per year to China, said event manager...