Many books have an Eastern Economy Edition so that people living in developing countries can afford them. I think it does help them make the decision in favor of buying the book and not photocopying it.
Is this price difference unfair ? Hardly. Consider a T-shirt (made in Bangladesh) that sells for say $10 in the US. It costs about the same in Bangladesh. So a bangladesi earning a tenth of what his US counterpart makes pays the same. In this case the person living in a developed nation gets a "discount" because of his location, and in case of books and software the person in a developing nation gets a discount because of his location.
A mathematician is a device for turning coffee into theorems. -- P. Erdos