I think what MUFC is trying to say is that MAN's catchment area is huge when compared to Liverpool's lucrative yet very defined catchment.
MancRy - The myth of MAN having a "huge" catchment area compared with other airports including Liverpool was well and truly 'de-bunked' during the RWY2 public inquiry and again when White paper on the future of aviation in the UK was published in 2002, when it was demonstrated that the airport with the largest population catchment in the North was actually Sheffield!!!.