Exactly! Why plant a bomb in a tree in the middle of nowhere??? (nowhere important strategically I mean)
It wouldn't be beyond the realm of possibility that someone doing something, shall we say, clandestine, might want to place some potentially lethal devices on the approaches to their lair to slow down approaching law enforcement officials or competitors?
Sorry, but sometimes things designed to kill, hurt, or maim are placed because someone is just plain nuts. Strategic value doesn't enter into it at all.
All in all? Wires coming from a cache are a really, really bad idea.