I agree with Q.G. It's a question of convenience. If you won't know what film you want to use until a moment before you need it, you probably need to keep at least a few rolls unrefrigerated. The bigger your film inventory and the more likely you are going to keep it until or past the expiry date, the more important refrigeration (and better, freezing) are. Professional film should always be refrigerated, at a minimum, whenever possible.