Hi there! I suppose it depends which part of Africa she is referring to. Certain coastal countries are more likely to have coconuts in abundance (right now East African countries come to mind like Kenya & Tanzania as well as Mozambique & West African coastal nations like Ghana & Gabon - to name a few). My landlocked nation doesn't grow any so they are certainly not
apart of our cuisine. I can find them at the green grocers though - they would have been imported of course. I am not sure how exactly they are consumed in general. We just enjoy the milk and the flesh too. However they are found in the food of other countries like Tanzania (Fish in coconut curry) or Zanzibari beans with a Coconut soup. (shown below). In my country however, if I hand a typical Zimbabwean a coconut you can rest assured that it will not find its way into a saucepan in any form.
Ummmm...there's coconut in there...

...somewhere