Not super familiar with Scribus, but with indesign it's a matter of starting your first page on the left hand side or right hand side, then having your master pages set appropriately on a double page layout. I found a novel template for scribus with a quick google, and the PDF they produced looks like it would be fine on a print job, with correctly alternating bindside bleeds. Maybe download it and borrow their parameters for the parts you need? http://johnosterhout.com/basic-book-template-for-scribus/

And, totally agree, I think a physical book is much better for something like rewards or marketing.