Curious.
Others might want to focus on the pointlessness of this for the Christian departed and his or her family, as it is Christ, the Lamb of God, who takes away the sins of the world.
I would wonder whether the custom has proved a means of salvation, not for those whose sins are thought to be “eaten” but for the sin-eaters. The “sin-eater” himself engages in an imitatio Christi, taking on himself the sins of others, not in God’s eyes, surely, but in the eyes of those who adhere to the custom, and being “despised and rejected of men, a man of sorrows, and acquainted with grief. . . despised. . .and esteemed not.”
Besides being pointless, why would anyone believe it?