Looks like a savvy promotion to me. It reinforces their independent image and implies that people all over Portland are being saddled with ereaders they don't want.
The article didn't mention how many (or few) Kindles they've actually taken in, which serves the store nicely.
From what I know of Portland...which comes exclusively from the new TV show "Porlandia,"...it may become the last bastion of the b&m DTB bookstore.