Runways are named by a number between 01 and 36, which is generally the magnetic azimuth of the runway's heading in decadegrees. From what I have read, most airport runways are aligned along an East-West corridor. Why is the North-South direction rarely used?
While there are many exceptions to east-west runways, generally speaking prevailing winds (which blow from a single direction) blow east-west rather than north-south. It happens because of Earth's rotation generates Coriolis effect.
There are other wind patterns besides prevailing winds. Trade winds occur near the equator and flow from either the north or south towards the equator. They curve towards the west due to the spin of the Earth. Polar easterlies blow close to the north and south poles. They blow away from the poles and curve east to west.
Hence, most of the runways are Eastish-Westish (not exactly East-West).
Runway directions are largely chosen both for geographic land features of the site of the airport as well as the average local wind directions. As most winds blow from West to east in the continental United States, most runways will be oriented approximately in that direction. There are some sections of central Kansas and Oklahoma which have runways predominately oriented to in north south heading due to the winds blowing largely in a latitude parallel or approximately thereof in that region.
I haven't seen the East/West bias that you reference, runways are typically built where they make the most sense. If there are prominent geological features such as mountain ranges or hills that could affect the approach, the designers may decide to construct the runway so that approaches and departures are not near the obstacles. Populated areas are another concern, if an airport is near a town, the designers may direct the departures and arrivals away from the town in order to limit the noise.