Is "The sweetest taboo" breaking one?

Carole Matthews, a popular author, has recently released a novel titled "The Sweetest Taboo", which includes sponsored advertising for Ford Fiesta. Ford has paid Carole to feature their cars in her book as well as in her upcoming novel. This practice is not new, as it has been done before by Fay Weldon, who was paid by Bulgari to include their brand in one of her novels. Fay Weldon did so with with pazazz when she named the book "The Bulgari connection".

Apart from writing about Fiestas in her novels, Carole has also been commissioned to write short stories about Ford cars that the company will use in their advertising.