"I've just read the judges' citation, which makes it sound exceptional,'' Richard Ebbett said.
"I don't normally buy long novels.''
Chelsea Nichols was buying a copy for a friend, having already read it herself.
"It's a really wonderful story,'' she said. "The win was well deserved.''
Unity Books on Auckland's High Street had put balloons in its window display alongside copies of The Luminaries to celebrate the win. Inside a sign by a stand of Catton's winning novel read: "She did it.''
Owner of the store, Jo McColl said the book had been selling "incredibly well''.
She said it was the "biggest selling fiction for about the last month''.
"I have never seen a New Zealand book take off so well from the moment it was published,'' Ms McColl said.
"The Luminaries just immediately went nuts.''