I travel a lot and talk to a lot of people and I can tell you from my experience that a lot of people don't know the best restaurants in their town. Most people haven't eaten at all of them to make the comparison. The best way to find out is to have some way to ask a bunch of people then compare their collective results and see what everyone's experience adds up to. That quickly starts looking a lot like Yelp.
I travel a lot, and I never ask for the 'best' place to eat. What you ask is very, very important. I always ask what their favorite place to eat is. That is a different result.
What I've noticed is if you ask a random stranger what the 'best' is, you get the same generic, expensive fusion something made into a paste cuisine. If you ask their favorite, you find small, off-the-wall places with terrible selection, but amazing food.
