I knew I'd forget a point or six in my previous post!
 
Ferrets on a meaty diet don't seem to want to chew rubber etc.  Does their
meal-time chew satisfy this urge perhaps?  Nor do they eat soap.  Soap is
made of fat, so maybe they are also satisfied with the fat content of their
diet.  As I've said, these are not answers, just observations which make one
think.
 
Love
Shirley, etc.
[Posted in FML issue 1588]