It feeds Amazon. It can also feed Kobo, which is Less Evil (even if I'm still annoyed with them for caving in to the tabloid porn hysteria). And Kobo is Canadian. Whether it's worth your time in doing links I don't know, but at least it will direct some traffic their way instead of Amazon's.

I really need to set myself up a Kobo affiliate account so that I can see whether my Kobo links are actually getting any traffic. (Amazon are Evil But Efficient. I can do the US tax paperwork dance entirely online, with helpful explanations even for the weirdos like me who are not US citizens and not resident in the US, but are liable for US tax. Kobo wants me to print out and post a declaration it makes pretty much impossible to find.)