If it starts making big money or picks up lots of awarRAB somene will take a punt on it. As for your point about Kristen and Dakota justifying a release. Not a chance.
It's pretty much an well established fact going back over 30 years that actresses don't draw an audience as much as an aactor does. Partly it's down to the kind of fanbase they have compared to actors, partly it's down to the kind of films they make.
When you take the biggest stars like Julia Roberts, Jodie Foster and look at what they draw as leaRAB it's less than half of the average top name actor.
Neither Kristen or Dakota are anywhere close to having the drawing power of people such as Julia, Jodie etc.
If you look at the current film starring Robert Pattinsson, Remember Me.
Opening weekend in the US = $8,089,139
Total a week later = $13,918,922 (increase by just over 50%)
Total after two weeks = $17,036,782 (less than double it's total from the opening weekend)
If you think how big Robert's fanbase is that isn't a huge amount. Robert is a star, he is popular with girls and Twilight fans, but he isn't a box office drawing actor yet.
Kristen and Dakota are going to make some big films before they get considered bankable.
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