Cannot Copy Requisitions Lines (originally from a Req Template)

We have a requisition template with non-inventory (expense) items.  The template allows expense items to be easily added to iProcurement requisitions via shopping lists. 

However, when trying to copy a previously submitted requisition that used that template, an error is received stating that the "Item was not added to cart. It is invalid for your organization. Contact purchasing administrator."

What is the problem?  How is this different than copying a non-catalog request requisiton?