In regards to "always on":
Always on items do exist, the question is how much are they allowed to effect the story? The Dresden Files RPG focuses on story mechanics, not physical ones. Fate points and stunts largely represent controlling how much someone can interact with the story.
Lets use Dresdens duster for an example. It is always enchanted with defensive spells, this doesn't change. However, it doesn't come up in the story every time he is attacked. It comes up, say, 3-4 times per story. It is still there, still enchanted, possibly helping in a fluffy way (man, if I hadn't had my duster on that fight might have been much worse), but only effects the story 3-4 times.
Now we look at that same item from an in game perspective. It has 3 uses, so it can come up in the story 3 times. The player can then exercise their story control (fate points) to allow it to be used more times. It is still magic, still working, but has no mechanical, story benefit beyond 3 times.
So your players can have magical protective auras, supurlatively sharp swords, and glasses that pierce illusions, and those things may be always active. However, their uses and fate points effect how many times they may effect the story per session.