Nothing. "There are no penalties for students who import books for their own use, under a 1998 Supreme Court decision that ruled that manufacturers who sell goods more cheaply overseas than in the United States have no protection against having their products sold back to the American market." Relevant article: http://www.nytimes.com/2006/03/29/education/29textbooks.html?_r=1
thank you for clarification. the books indeed can be printed legally in India: "The textbooks are printed legally in India under copyright arrangements worked out over the last decade by American and British publishers." but in the case with amazon what they are doing is illegal: "But businesses or individuals who buy books for resale outside India could face prosecution for copyright infringement."
Was it an Amazon Marketplace purchase? If it was, Amazon aren't buying the books for resale. The book was bought directly from India as an individual. [EDIT: Just re-read your original post. Associated retailer is a third-party. Amazon just facilitates the transaction]
How much would Amazon take as a profit on such a deal ? I always wondered how much profit they make on selling a second hand book for 1$ or so.
Internet is imploding commercial real estate http://www.nytimes.com/2010/08/31/nyregion/31barnes.html