absorbtion - would imagine it's the same principle as the need to soak earthenware plant pots before planting anything in them - this enables the earthenware to become saturated and therefore it won't draw as much moisture out of the soil.
Is that the same as dehydration via alcohol? Love the Davy Crockett hat by the way. Remember getting the full outfit when I was a kid. Thank God there are no surviving photographs.