Duct tape works as a trap, but be sure to put it where wandering lizards and mice aren't likely to come across it. It's not at all a humane thing to do to vertebrates.
I've used the scent traps, and they work well. They catch so many moths! But, again, put them where vertebrates can't reach.
Diatomaceous earth is unlikely to work. Just freeze the bag, then seal the feed up in an airtight container from now on. Plenty of places sell pet food containers, and any large enough tupperware or other food storage bin will work fine.
They aren't that big a deal, though. People care about...