I've never refrigerated or frozen sugar; but do refrigerate flour and those type products; things will 'hatch' out of the flour products, eventually if not used and recycled out frequently. I'm not so sure it's the critters that 'find' the flour products as them hatching out of the product if not used often. Either way it's disheartening to find bugs crawling around in your crackers or flour. Ewwww