The ten pack of results at the top for certain keywords under google local/maps pushes down the organic search results below the fold.
The results in local/maps are based on an entirely different algorithm then organic search. Textual based content and links have little value in boosting a google map listing. It seems to be more based on 3rd party review sites such as yelp, yellowpage like directory websites such as infousa and blog content.
Thus minimizing the traffic to these organic results and undervaluing their seo, as a poorly optimized site that is listed as letter G in maps will be higher on the page than the top organic result!