The same happens, for instance, if somebody says "the park"; I don't get a mental image of the park, I just start thinking about things associated with it (typically things that happened there).
I can do the whole "visual memory" thing, but it's a conscious process that I have to focus on, rather than something that comes automatically. That's not to say my visual memory is bad, just not default.
I always figured this was how nearly everyone thought, but after reading this thread I'm questioning it now.
EDIT: also there's some kind of search tree balancing going on, I think. Because sometimes you may ask me what happened in January, I feel like I sort of mentally go over everything and do a quicksort type of process? But only if there's a lot of past events that aren't already associated with the January tag? I don't know it's hard to explain.