Keeping beer cold will slow the oxidative processes that cause staling, so we recommend refrigeration to maximize the shelf life and insure that the flavor remains as true to our intentions as possible. This remains, however, a recommendation and not a requirement.
All beer will stale over time; that much is inevitable. To combat this, we go to considerable lengths on the brewing side to minimize the overall potential for oxidation, primarily by protecting against inadvertent exposure to oxygen throughout the process. Some staling will still eventually occur, which brings us to the storage conditions. Oxidative reactions are like any other chemical reactions: they accelerate as the temperature increases. By keeping beer cold, these processes slow dramatically.
Fortunately, the staling process doesn't occur very quickly at typical ambient temperatures. With proper stock rotation and good sell-through, a retailer may store any Bell's brand outside of a dedicated cooler and the beer will be as fresh and equally enjoyable as beer from any other retailer. Once you get it home, if you have an abundance of refrigerator space, by all means keep all of your beer cold. Otherwise, stash most of it in a cool, dark place and just refrigerate what you can.