Pat-
  I did not think you were questioning my knowledge about the house.  No
offense was taken.
  As for why the family would have done such a seemingly bizarre
thing?  That is the $100,000 question.  The Schroeders were VERY
conservative  . . . and very frugal people, which may account for the
conversion from a factory to house.  To the best of my knowledge this
change in usage is not "typical."  Any other opinions from those lurking
on the list?
   The family manufactured saddletrees (the wooden skeleton upon
which leather and stirrups are applied to make saddles).  The
saddletrees were wrapped in rawhide to add strength to the product
and create a unified whole.  The vat house was used to prepare the
hides for this purpose.
   All in all the site is quite curious.  It will probably take years to puzzle
through these and other oddities.
Regards,
Debbie Rotman