Imagine that the kids in a family blamed broken items discovered around the house on "Todd."  When the parents ask more about Todd, and ask the kids separately, they get conflicting answers about Todd’s height, skin color, personality, and so on.  These facts would count as evidence against Todd: 

• The parents have never seen Todd, though they are around often.

• The kids want everyone to believe in Todd so less blame will fall on them.

• The kids give conflicting stories about Todd’s features.

This seems similar to disagreements about God, and addresses the question Nick raised about Hal’s comment.  The facts that religions disagree about God’s features, that they have reasons to want to believe in God even if he did not exist, and that skeptics find it hard to find independent evidence for God beyond what supporters say, all suggest that religions are independently making up this story of God.

Added: I wonder how well a similar structure could rationalize other situations, such as in morality or paternalism, where some want to take disagreement as evidence for skepticism.