Where the Nigerian guy's activities are concerned...I believe that sometimes especially where security is concerned "racial profiling" or segregation based on nationality or origin, age group, creed is a necessity.

Profiling is generally based on statistics or past experience. A certain age group (for ex 18 - 25), from certain countries (ex Nigeria), of certain creed ( maybe Muslims) are more likely to indulge in threatening activities.

I have been profiled during my travels to the West. Its frustrating, but at the same time, I feel more secure in the knowledge that when I travel from my point of origin A to point B, there are more chances of me making it to my destination alive. So go ahead check me, my baggage ,everything, even if it means offending by racial profiling, I dont care. Just make sure that no crazies get aboard my flight.