But at least Christopher Nolan does. From Wired:
"I’ve always believed that if you make a film with ambiguity, it needs to be based on a true interpretation. If it’s not, then it will contradict itself, or it will be somehow insubstantial and end up making the audience feel cheated. Ambiguity has to come from the inability of the character to know - and the alignment of the audience with that character."