Oakland is known for its food trucks, which serve everything from tacos and tamales to West African cuisine. But few know that this latest culinary trend got its start in Fruitvale almost 30 years ago. Fruitvale still has the city’s largest concentration of mobile food vendors – a predominantly immigrant population. These micro-businesses provide owners low overhead and the opportunity to become successful entrepreneurs. But if running a small business isn’t hard enough in this economy, vendors now face the added challenge of armed robbery.