Apparently some stores accidently sold copies of the latest Harry Potter ahead of schedule:

A drug store accidentally sold a copy of the latest Harry Potter book to a woman ahead of Saturday's strict release time, but the customer said she will return it.

Mandy Muldoon said she was shopping with her 9-year-old son when she spotted a stack of the much-anticipated books on a shelf and purchased one. Christine Ekblom, a manager at the upstate New York pharmacy, said she believed it was the only copy sold.
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Fourteen books were accidentally sold Thursday at a grocery store in Canada, but a judge ordered the customers not to talk about the book, copy it, sell it or even read it before its official release.

Muldoon's husband said the family would return the book to the publisher, though his stepson, Sylum Mastropaolo, admitted reading about two pages.

"We're going to do the right thing," Mike Muldoon said. "We don't want to ruin it for other kids and take away from the experience of everyone reading it together."

That poor boy. He sounds like he is apologizing for a crime... reading a book which he bought! How dare him! Yes, the store goofed, but I sure as hell wouldn't return it. I would read it, and enjoy it. After all, that's what a book is for. Would I publish copies on the Internet? No, but I wouldn't normally do that anyway. As for owning the book ahead of time ruining for others... ummm... the simple solution to not ruining it for others is not to tell others what you read. Duh. I would hope you wouldn't do it even after the release date to people who haven't bought the book yet. And for a judge to decree that you're not allowed to read a book that you own before a certain date... are you kidding me? How Draconian is Canada going to get?