- Hip-hop is the perfect medium to register the relevance of contemporary brands. Hip-hop and rap have always been about the here-and-now, rather than rock or pop songs, which typically focus on eternal themes of love and loss.
Another explanation is that the vocabulary of mainstream hip-hop (or "rap" as some call it, with the word "hip-hop" being reserved for more credible music) has become restricted to assertions of status and power, which is why boutique brands are so important in the genre.
(Hip-hop has disappointed me; once upon a time, it was all rather clever and intelligent -- it started off as an African-American equivalent of punk, using improvised technology (such as turntables) in much the ways that chip musicians do now, with all the resourcefulness that such a new medium entails -- but now it has become rather stupid and atavistic, all about booty and bling-bling and how bad you are and what you'll do to whoever challenges you. Mind you, the definition of "hip-hop" appears to have been lost along the way as well; case in point: Universal's Def Jam division rereleasing a DVD of Al Pacino's Scarface rebranded as a "classic hip-hop movie". I didn't know that this movie contained any rapping, scratching, breakdancing or aerosol art (the "four elements" of hip-hop culture; note the absence of pimpin', bustin' caps or wearing bling-bling jewellery in that list).)