""One thing that I don't understand though is why a canned product has to be chilled? Surely the whole point of the sterilized and airtight environment of a can is in order to negate that need?""

Likely to prevent the growth of botulism. Unless a product is retorted (steam heated to kill all bacteria), there is a possibly of anaerobic bacterial growth. Fortunately, few products and surfaces, in food preparation, are certified sterile from a food preservation perspective.