The $40s deals are marketing gimmicks... It created excitement & demand for new flights...
I am sure many Kenyans (I almost flew to Gaborone) took advantage just to check the new destination... and if they like Gaborone,Kisangani,etc... they may fly there again at the higher rate...
The 'cheap' offer excludes taxes... and probably creates more excitement than (expensive) full page ads would... or TV spots...
The UK fare is very restrictive & competes against the other airlines...
Greedy when others are fearful,Very fearful when others are greedy - to paraphrase WB
Greedy when others are fearful. Very fearful when others are greedy - to paraphrase Warren Buffett