My first thought on this one is, well, they show the candle being used as a safe, and then they show the candle lit. Would you really want to light a wax container that has your folding money hidden inside? Also, "candle makes a super gift"... but when you give it to a loved one, wouldn't they get suspicious that you know where they're hiding their valuables?
Candles, shelves... and I've seen shaving cream cans, Ajax canisters and STP motor oil containers in other catalogs with secret compartments. You know, I bet, somewhere there's a book or a Web site where you can see a list of all the household objects with hidden compartments. So if you decide to burglarize a house, you'll know exactly which items to examine. "Let's see... white candle, yellow plug on the bottom. Check. Triangular corner curio shelf, secret drawer. Check."