what's up with this movie's A list cast?

well, Shannon was cut out of the movie (good for him) and Fassbender was by far not as popular as he is today as the movie was made. For the others, I don't know... Malkovich probably needed the money and Brolin is one of the people who is responsible of this mess because he wanted a lot of rewrites of the script and that's why the writers (and also supposed directors) of the film dropped out. I was reading the original script and I have to say it was pretty cool, but also very violent. But with them dropping out because of Brolin, the whole thing became a mess.