I hear you, for sure. But, I doubt that the contents of the back of a UPS truck go for 60 straight hours in this kind of extreme temperature. I'd think drivers would keep the heat cranked, at least during their 8-10 hour shift. But, you may very well be right. Maybe someone who has courier experience can chime in?
french16, it's got nothing to do with the humidity, remember your basic physics. If you drill holes in stone, fill them with water that later freezes, voila: Cracked stone through expansion. Early road builders used this trick in the mountains. The expansion needed to push up a cork is minor by comparison.
Chum lee, interesting, I'd be curious to find out if a very cold, but non-frozen burgundy or such is negatively affected by the chilling.
Icewino, for sure. It's -6 here now, and should bottom out around -10. It'd take a hell of a lot of insulation (more than the styro shipper for sure), to keep the cork down during a whole evening out in the elements.