Most all large department stores have some sort of loss prevention program in place. They routinely use psychology to deter shop lifting by creating the overwhelming impression of being watched. It starts the minute you walk in the front door. What is the first thing you see? That's right! It's you walking into the store. Why do you suppose that is? It's because this camera location deters shoplifting. This technique is simple, inexpensive and it WORKS!
Don't have a big budget? You can still take advantage of this technique. All you have to do is buy 1 real dome camera and plug it into any standard TV with video inputs. Mount the TV on the wall or ceiling near the front door. Add a few dummy domes through out your store and presto, you have an effective camera system deterrent.