Zazzle Christmas products, or products for other occasions, can serve the obvious purpose, but other purposes are also possible. Whenever you realize there is another use, point it out. In a previous article I mentioned selling cutting boards also serving as serving trays. And even Zazzle now advertises some heat resistant coasters as useful for trivets.
Sometimes, an occasion might bring forth a different use.
When designing a product think about how other uses will impact the visibility of the image, and design with that in mind. We will get to that shortly.
Do not limit your sales possibilities. Even if a use is obvious, point it out in the tags and description.