Is it because ther's a higher proportion of pores in the nose area? anyone recall pushing out the 'white worms' as a teenager! Neutrogena does rank well I think for off the shelf products dealing with greasy skin.
The skin is incredibly thin in the nose area, directly on the bone with very little flesh to pad it out.
The nose is the most prominent part of the face and is the first to be affected by weather - sun, wind and rain.
Many people have a greasy T Zone - forehead, nose and chin. All much bonier than the cheeks.