Locked Doors in Wilderness Locations from BitF

[Nachie]

So in Blood in the Forest we have some new wilderness locations on the forest boards that only take up one space each. In the rules it states that any side of the building may be considered both a door AND a wall, so that essentially any of these buildings may be entered into from any adjacent space. The rules even specify that you can enter into them DIAGONALLY.

Shortly thereafter the rules state that the zombie player(s) may use locked doors on these buildings as normal, but how on earth would this work?

Because all adjacent spaces, even the diagonal ones, can be counted as entrances, some of these buildings have like 6 "doors" that the heroes can use to enter and exit. So to effectively keep them from going in or coming out, does that mean that a zombie player would have to play SIX locked doors? Including on the corners? Sure it will still stop a player in their tracks the first time you play it, but this almost makes it seem completely useless to waste a good locked door card on the wilderness locations.

Just wondering if anyone else had a different interpretation of the rules.