It's expensive to have boots on the ground in every zip code. RedFin hires their own agents full time. OpenListings and Zillow refer online buyers to their affiliated agents who cut them a deal on commission in exchange for leads. You can always list a place with photos and all on Zillow or CraigsList and mention that seller will not pay an agent's commission. End of the day there's a "For Sale by Owner" sign for those driving or walking by.

But considering that in the US it's the seller who pays both agents, there are no immediate savings for potential buyers, and some, being new to the home-buying process in general or new to that zip code, would prefer some hand-holding and chit-chatting provided by their agent at no cost to them.

Among some not so obvious valuable tidbits that the buyer's agent can provide:

* general feel about the neighborhood, whether it's on the rise or in decline

* previous scandals and issues, like contaminated water, city attempting to pass an additional levy or tax, house being on the airport path, etc.

* potential future improvements, like a light rail station planned nearby

* referrals to various local professionals, like inspectors, surveyors, painters, or movers

* any other new developments in town or neighborhoods that the buyer might not have considered, especially when shopping remotely