Wineries normally 'cold stabilize' a wine to prevent this happening. To do with tartrates falling out of solution when a wine is chilled. Wineries only do it for asthetics, to avoid questions like this. The wine quality should not be affected.
Ever enjoyed a fine single malt on the rocks and experienced the same phenomonen? Same thing. It is only asthetics. All white wines are generally cold stabilized, very few reds are. Wineries assume people wont chill their reds, and if they do, they wont notice cloudiness of crystals through the darker glass.