Grindhouse No More

I’m late to the party, but I just learned that “Grindhouse”: will be split in two in Europe, and later on in the US, as well. Audiences don’t seem to get the concept of two cult-style films mashed together with fake trailers. At least extra material, meant for the DVD, will be added to each standalone film. Personally I’d have loved to see the film as the intended double feature. So why no limited-run arthouse release?