Imjayisthatok - we didn't use the electric fence or the turret yet in the easter egg - what makes you think we have to use every buildable? If I'm wrong, please cite a youtube video of them actually using it in the easter egg. We've only used 2/5 buildables (turbine and Jet Gun).
Also, The shield is made of glass, metal door, and a wheely dock. The door isn't particularly shiny, glass refracts light, and you can't get the wheely dock to easily face the lights, unless you set it down. Treyarch really does know their stuff, and they implement it accurately and well - aside from the entire zombie concept, time travel, and teleportation.