Hot 100 from Billboard

Here is a link to the Billboard's Hot 100 chart. Alot of rap songs on there but why is this not translating in record sales? Many answers but let's save that for another topic.

Link:
http://www.billboard.com/bbcom/charts/chart_display.jsp?g=Singles&f=The+Billboard+Hot+100

Da Chartz

HipHop Sales for the week of 2-15-09 according to HiphopDx

Link: http://www.hiphopdx.com/index/news/id.8587/title.hip-hop-album-sales-the-week-ending-2-15-09