Not only can the neighbors tell you about the house you are buying, they are actually an important component of its value. A home doesn't stand alone, even if you are on 5 acre parcels.
Most people live in a neighborhood - what's it like? Are they open, caring, friendly, but non intrusive... or are they overbearing and delving into your life. Or vice versa, a reclusive. Who has the out of control kids, dogs, etc. - or is all peaceful in the 'hood?
Build enough rapport with the neighbor and you could learn all kinds of things about the house you are considering. They can be quick to disclose if the Seller had sewer line troubles, roof problems, or any other quirky thing that can impact your home ownership tranquility. You are the newcomer, the new neighbor, the one that will be living there if you buy the home. The Seller is leaving. Who do the neighbors want to befriend?
Its good to check in with the neighbors if you want to know what's going on.