The roots of this form lie in jazz, blues, rock and reggae. It is unique in it's melding of these forms, and mastery of rythmic and original spoken word stylings, makes there particular form the closest to the mother land. Each rhym is like an African chant. It is related, and yet evolved. The commercial aspect of the business has solely to do with the making of money and understanding what sells.
Industries know that sex, violence and scandal sells.
Companies are fronting the money and unfortunately have a say in the product. This is not unlike the communist having their say in the Harlem Renaissance. That happens with any art form. Even African prints are sold commercially. Maybe that also makes us smart entrepreneurs.