The shift in burger culture from tits worship to ass worship is a result of ethnic demographic shifting. In the 80s to even the mid 2000s the ideal was a white blonde woman with a small ass and big titties, some Michelle Pfeiffer/Jenna Jameson/Britney Spears looking chick. With the rise in popularity in hip-hop and shifting demographics, women having a large ass, as seen more with black/latina women is seen as desirable as well as other non white-european centric beauty ideals.