I love the forum with the photos... Anyway, I'm working in a house removing drop ceilings in several rooms. One was the bathroom (the pic with the finished walls). It may be hard to see, but there is a hole punched into the ceiling sheetrock where two wires come down and are connected to the flor. fixture, and an old incandescent fixture. No boxes, no sheathing... nothing. I haven't been up in the attic yet... gulp. The foil was all around the ceiling and used (I guess) as a reflector.
The next batch comes from the basement office where there was some water damage to the sheetrock. When I pulled it down, I couldn't believe what I saw. In these photos, you'll see a box with a receptacle and two plugs. These came from two recessed flor. fixtures. They were located in the stud cavity, but the box was not in the same cavity as the fixtures thus they were concealed. You'll see in one photo how the ceiling joist was carefully notched to accept the SJ cord. No nailer of course... and this ceiling was nailed sheetrock with nails just a fraction of an inch away from this cord! You'll also see a junction box (also concealed) with unprotected wires coming out of it and again no nailer at the studs.