Why aren't bottles stored on their sides at wine stores?

Hello there! I'm Dr. Vinifera, but you can call me Vinny. Ask me your toughest wine questions, from the fine points of etiquette to the science of winemaking. And don't worry, I'm no wine snob—you can also ask me those "dumb questions" you're too embarrased to ask your wine geek friends! I hope you find my answers educational, empowering and even amusing. And don't forget to check out my most asked questions and my full archives for all my Q&A classics.
Dear Dr. Vinny,
We’ve all heard that wine bottles should be stored on their sides. Why then, in stores, are the vast majority of them upright?
—Jerry, Minneapolis, Minn.
Dear Jerry,
You’re right that a wine bottle sealed with a cork should be stored on its side, which keeps the cork from drying out. A dry cork can shrivel up and let air into the bottle, causing the wine to prematurely age and the cork to crumble when you try to remove it.
But it would take more than a few weeks or even months of standing upright for the cork in a recently-released bottle of wine to start showing signs of age. A busy wine shop will have a quick enough turnover that there’s no danger the wines will be sitting there so long that the cork could dry out. But for special bottles, you might want to look for a wine shop that gives their wines some more care.
—Dr. Vinny