Second hand shops often have large storage jars, the kind with the metal wire closers, for a fraction of new cost. Replacement rubber rings are available, check anywhere new jars are sold, or online. Jars like this are great for bulk storage. Not only do they keep moths or other pests out of the food, they can keep moths -in- a jar and NOT contaminating all the rest of your food. I put all my dry-goods in glass and I've had no trouble with pests for years.
Moths will chew through plastic bags.