I think the case hinges on the context of the usage of trademarked property. Because the images in question use the trademark as an integral component of the message conveyed by the image, this constitutes a violation. In other words, because the photograph is about the air freshener's relationship to the scene, and the implication that something is being freshened as a result of its presence, then this violates the trademark because the photograph's predominant message is one advertising the use of the product in some way. It's not incidental, but central to the image.
By contrast, if one took a stock photo of, say, a frazzled accountant during tax time working late hours, and there happens to be a Swingline stapler or Bic pen or Casio calculator on the desk, there would be a much weaker case for infringement under similar grounds if the subject of the image is clearly the accountant. The products depicted and their trademarked designs are not the focus of the photograph, so a reasonable person would not construe the image as advertising the use of these products.
But if the photograph took the image in a way that made the stapler, pen, or calculator the raison d'etre of the image, that would change the situation, and fair use probably would not apply.
I have taken notice that TV commercials, movies (for years), and some ota programs 'tape out' names of cameras and other products. Recently they have been fuzzing out T-Shirt logos. So, obviously their lawyers are telling them to be cautions.
