In the AddressPoint shapefile, if you filter by "PLACENAME" = 'Chicago' , then you get a large number (on the order of 10^5) of points that all over Cook County but are not in Chicago. Also, some of the points have 6748 N Greenview Avenue, Chicago as their address, but those points are located in Hyde Park or SW Cook County.
In the AddressPoint shapefile, if you filter by "PLACENAME" = 'Chicago' , then you get a large number (on the order of 10^5) of points that all over Cook County but are not in Chicago. Also, some of the points have 6748 N Greenview Avenue, Chicago as their address, but those points are located in Hyde Park or SW Cook County.