Here’s a way we take vicarious actions seriously in the West: at Christmas time, it is common—at least in my observation—for parents to buy gifts for their children to give to others. Often, the children don’t choose the gifts, and are only told what these are after they are purchased. That the gift is from the child is a “legal fiction”—yet when Grandma opens it, she, the child, and everyone else take seriously this legal fiction. She thanks the child. The child says, “You’re welcome.” Others praise the child for the gift.
I’m not suggesting that this is analagous to vicarious atonement; rather, I’m pointing out that the common Western intuition that vicarious atonement is unreasonable is unreflectively selective. We can see vicarious legal fictions in many facets of Western civilization, including not just in presents, but especially in politics; such as in the common intuition among staunch critics of Christianity that white people share some kind of guilt for the actions of their slave-owning or Maori-conquering forebears. To claim, therefore, that vicarious atonement is intrinsically unbelievable is not only to elevate one’s cultural conditioning to the status of moral fact, but ironically to also be blind to many aspects of that cultural conditioning which mimic the same vicarious mechanisms.