I think what you want in a pull is really just "git fetch", which will update all remote branches. In case you haven't realized this separation, try "git branch -av" to see that your local branch names are distinct from all the "remotes/*" branches. Also, if you have more than one remote repository location, not just origin, then "git remote update" will fetch them all.

Pull is basically the combination of fetch and merge into your local branch. Since there's always a chance for merging to fail and require fixup, it would be dangerous for pull to try all your local branches at once.