More than rides, pigs or curly fries, people are drawn to fairs by big-name entertainment, says Douglas County Fairgrounds Manager Harold Phillips, citing national surveys. Popular acts drive overall attendance and vendor sales. Fair food vendor Ron Leonardo, owner of Leonardo’s BBQ in Roseburg, fondly remembers 2010 when the Scorpions drew a record crowd of 12,500. “It was unbelievable, the attendance for that show, record food sales too,” he said. “They definitely go hand in hand.” The 2013 lineup Phillips announced Thursday follows a proven formula — two rock bands and two country singers. No blues, gospel or cover bands. …