People maybe figured out a while ago that Tarantino was sorta telling the story of this stylish ultra-brutal popculture obsessed world (Conversations in Reservoir Dogs, Meez in Pulp Fiction) and in Kill Bill we got to see what the cinema WITHIN that world was like... Then we saw in Inglorious Basterds sort of how that came to be, with cinema being so essential to the conclusion of WWII in that canon that cinema seems very important and real.
I figure what he's doing here is telling a story set within the Hollywood of that world to show the sort of crazy environment in which your Kill Bills get made. That's my guess.