Or perhaps it was just easier and cheaper to fabricate a sheet-metal box with one side die-punched with a grid of holes. I can totally see how making a cage of

Or perhaps it was just easier and cheaper to fabricate a sheet-metal box with one side die-punched with a grid of holes. I can totally see how making a cage of wires might use less material, but be magnitudes harder to fabricate correctly (electrically, mechanically, and aesthetically) and get right without any leaks.