Don. Both of your analogies are far fetched. If the 'crate' in the museum was part of the art, then that would be closer to represent unopened playing cards (which would be appropriate to display as is). The analogy with the milk and cereal is even more ridiculous. People buy cereal to consume. If people bought cereal simply because they like the art of the box, then they'd put it on display/keep it in their collection and thus would not bring it out to want to consume as it would not serve that purpose (Thus the analogy is incorrect).
Personally i like to open most of my decks. However i completely understand why some collectors like to keep them sealed. Sealed decks not only serves as a collectable that will generally increase in value over time, but the deck box itself is also a work of art. Think of it like wine. Why do people buy expensive wine to add to their collection, but never open them to consume? As soon as you pop that cork open, the value decreases close to zilch. Of course some people will open expensive wine because they are curious about its content, its history and its flavour. Whereas some would rather it sealed and are happy to simply display the bottle as it is. Playing cards are similar.
Playing cards are ephemera - items that are intended for consumption and not made to last very long. It's why vintage decks are such a big deal, especially sealed ones.
Even if the crate the art is in is beautiful, it's still just the crate - it's meant to hold the art.
The breakfast analogy was pushing it a bit, but cards were also meant to be "consumed" - they're PLAYING cards, first and foremost. Perhaps a better analogy would be comparing it to buying a board game or a chess set to display the wonderful box, unopened and still sealed, on your shelf, never once playing it - hell, you might not even know HOW to play, you just like the box that much. It's collecting largely for the sake of collecting, period. That's enough for some - it's not enough for me.
Wine is not a good analogy - only good VINTAGE wine gets saved, cherished, etc. Most wine is moderately inexpensive and not meant to sit on a shelf forever - it just turns to vinegar in a small handful of years. (Especially if it's sold in a can or a box!) Those wines, the wines most people can afford and buy, are NOT meant to be collected, just consumed.
I'd say cheap mass-market decks are the wine-in-a-box variety, while custom decks are the decent name brands usually bottled within the last few years or so, even if they are limited editions. If there's enough of them lying around in the future to meet the demand for them, they won't increase much in value at all. Remember the big to-do over the "Death of Superman #1" comic books? People bought them in droves, thinking they'd become this big-deal collectible they could sell to put their newborn through college in nearly twenty years. The thing of it was, despite being "rare" and "limited", there was enough of them around that any demand for it was satisfied, and the demand didn't increase over time - it dropped when it was later revealed that Superman came back to life. Comic book stores have too many of them choking their inventories - it wouldn't surprise me to see them being shredded for the bottom of the owner's hamster cage. So much for putting Junior through college, right?
