Come read my Arkham Horror stories on Twitter @ArkhamHorror
Image courtesy of Smizmazmarlemagne
We don't really know if you draw a fixed number of those locations out of the box at random, or if we have to use all of them, if that's what you were asking.
In the image comments Marco says you won't use all of them (the woods encounters, at least) in every game leading to more replay value. Since he actually has the game and the rules, we can probably trust him on it.
Doesn't mean it will be true for any other locations in the core, of course.