Too many people drink champagne for one reason: to wash down wedding cake. It may surprise many of these revelers to learn that champagne and wedding cake don't make a good pair. Champagne can be a good wine to serve with appetizers or a meal because it goes well with many things, but sweet desserts is one of the main things that it doesn't match.
Champagne is generally light and acidic, with varying degrees of dryness. The bubbles in champagne help cleanse the palate, another characteristic that makes it go well with a meal. Champagne goes especially well with salty snacks.
Other people drink champagne mainly at special occasions like New Year's Eve. Too much of it without food can lead to a hangover. It also tastes acidic on its own, so it works better as a meal accompaniment.
If you're new to wine tasting, there's something you should know: Only wines made in the Champagne region of France can bear the name. Some sparkling wines made in the United States and elsewhere are similar, but they aren't champagne.