Gifting iBooks is Great (but let me keep the receipt)

You can now gift anything in Apple's App, iTunes, and iBooks stores to another user, as long as they're in the same geographical region (sadly the world of international licensing has a long way to go). 

If it’s digital books your family and friends love to read, Apple has a gift for them and for you. After long being the company’s sole online store without gifting options, the iBookstore now allows you to send ebooks to your friends and family.

It's a great and necessary convenience, but whenever I've given a digital download as a gift I've wondered whether the person I'm sending it to already owns that particular album, movie or app. While it would be great to get confirmation from Apple that they didn't have it (or that they'd added it to a wishlist)  I can only begin to imagine the privacy implications. A safer option would be for Apple to let me include the digital receipt, and to allow the recipient to exchange it for something else (prior or downloading).

Would that cause problems with the way way Apple recompenses publishers? Do they credit the sale when I buy the gift, or when it's downloaded?