In the states, HESS was (is?) a chain of gas stations. When I was a kid, they used to sell a toy truck around the holidays (and possibly other times of the year), and I always got excited when the new one would come out. I think that all of the white on this Prime kind of pings the HESS nostalgia feels for me.
Regarding another point in your post, I am not surprised that they didn't throw a little more stank on him in the form of a stocking cap, tree, reindeer, star - anything that would further drive home the "holiday" theme. If we lived in less economically turbulent times, I would be surprised, but not now. As it is, they took the existing Prime trailer, blasted it with white, threw a few red stripes on it, and called it good. Kinda boring, IMO, but I am glad for those that like it.