I have a correction and an additional piece of advice to add to my food thoughts from my review of An Economist Gets Lunch.
The correction: Tyler Cowen does mention how to use food websites. His advice is to only go to new restaurants who have recently earned their ratings and then to search for where to find the best specific dish rather than the best restaurant to make sure you are getting advice from people really interested in the food. I still think that adjusting reviews for the type of restaurant and consumer can be more helpful, but he did address using internet reviews to find food.
The advice: If you are at a festival that sells food there is an easy way to find good food: Find the food trucks. The other food booths have persisted in environments with mostly captive customers while food trucks compete on the basis of cost and quality with normal restaurants everyday. Eventually food trucks will push up the quality of the food booths at these festivals or raise their prices while at these festivals to capture more of the surplus, but it's still the surest path to decent food. As an added bonus, if the cell network is not too overloaded you can check the reviews of food trucks before you pick where you are getting your snack.