Having spent a few years planning and executing a local 'taste of' event in my own neighborhood, I know how challenging these things are to get right. Small restaurants often don't have the capacity to staff the event and keep their doors open at the same time. Successful restaurants don't need you - and can quick to show you the door if you haven't developed long-standing relationships over time. Add to that the challenges of keeping volunteers from burning out over time (that one I know from personal experience!), and you can easily see why these events start with a bang, but can fizzle quickly.
In New York, we have the 'Vendy Awards', a non-profit event that aims to recognize New York's best street vendors. As Amy Kantrowitz, two-time managing director of the Vendy's notes in an interview on American Express' Open Forum, three things can go wrong: failing to deliver on your promise; making people wait on long lines; and not having enough food. This article talks about the basics of getting a food event right, starting with setting expectations and setting prices that reflect those expectations. She also talks about the details of event planning and volunteer recruitment. Given the fact that restaurants often form a vital niche for so many urban commercial districts, getting a food event right is even more critical!