Black/African lesbian porn

[LezNymphoLuvsFeet]

Porn featuring Black/African lesbian/girl-on-girl scenes are rare in mainstream lesbian porn, especially if not counting interracial scenes. It seems only Arab and Indian scenes of that kind are even more rare.

Any theories as to why that is?
(Asking this, of course I realise that at least 95 percent of "lesbian" porn is made primarily for the male audience, maybe that somehow is part of the reason but I still wonder.)