David Malki over at Wondermark recently delved into what he calls the "Oenophile's Quandry".  When is an occasion special enough to merit that special bottle of wine?  It's a common problem facing those with collections of tasty beverages (see, for instance, this conversation over on Snooth), and I have in the past encountered champagne past its expiration date because that special occasion never arrived.

Psychologists have examined this problem, too, and perhaps it's wiser to approach it from that point of view instead of the economist's.  Basically, opening that special bottle is a special occasion all on its own, so please go for it.  Drink up!