The Klaarwater Hottentots distill a spirit from the berries.
The Bushmen from Botswana use the fruits to make a beer. Fruit often appears in their folktales.

Khadi (the name of a native drink) appears to involve multiple plants including the fruits of Grewia species.
Grewia species have been reported to contain many alkaloids including traces of B-carbolines.
The production of the brew khadi is known to have arisen after the introduction of sugar by the Europeans but there is a distinct possibility that the plants involved reflects a prior ethnomedicinal familiarity to indigenous people.
While the primary intoxicant of khadi appears to be alcohol, the complex of plants involved and the potential pharmacological interactions is an area in serious need of in-depth study.

(We have several other Grewia species' seeds available.)