I think the biggest brazilian online bookstore does this with (imported?) books: if I search for, say, "Types and programming languages", they say its imported

I think the biggest brazilian online bookstore does this with (imported?) books: if I search for, say, "Types and programming languages", they say its imported and will take 6 weeks plus shipping time to get to you. They never mention they are going to buy a single copy from Amazon for you and put some % on top of it. I don't know how they implement it to integrate with Amazon book list. I could do it for less % though... On the other hand, they are providing some value: isolating customers from changes in USD rate and providing customer service.