Slap the word marriage on the front of a product, and suddenly it becomes much more expensive, or so the joke goes. Alas, the wedding market's no longer laughing. As fewer couples walk down the aisle together, the companies who cater to brides and grooms have begun to suffer.

You may now dismiss the bride
According to The New York Times and The Wall Street Journal, census data reveals that fewer young people are getting married than ever before. What's more, for the first time since the U.S. started tracking matrimonial trends, more people of typical marriageable age are now single than married. The staying-single trend applies regardless of geography, race, or gender.

This doesn't necessarily suggest a lack of romance or commitment among the nation's singles. The number of unmarried cohabitating couples has surged, and while many of those may end up married one day, plenty of them aren't in any hurry.

This trend may signal changing social mores, but it's at least partially attributable to the poor economy. Given high unemployment and a fair amount of uncertainty about the future, lots of young people might feel like it's harder to justify pricey rings, a big wedding, and the other usual accoutrements of marriage, which can blow a budget or result in massive debt. Even if happy days do return again, the trend away from marriage is already very well-established.

As a result, companies that capitalize on weddings' tendencies to inspire consumer splurges could face a rockier road ahead. The Knot (Nasdaq: KNOT) owes much of its traffic to wedding planning. Tiffany (NYSE: TIF) and Blue Nile (Nasdaq: NILE) are both go-to locations for diamond engagement rings. Diamond rings and engagement rings represented 21% of Tiffany's total sales in 2009. This category had the highest price point of Tiffany's four major product categories, at an average of $3,300.

In addition, other players are trying to use the wedding market as an ancillary revenue source. J. Crew and Urban Outfitters (Nasdaq: URBN) have recently delved into wedding-oriented initiatives. Companies that offer popular gift registries -- Bed Bath & Beyond (NYSE: BBBY), Williams-Sonoma (NYSE: WSM), and Target (NYSE: TGT), to name a few -- could also lose sales as a result of an anti-wedding trend.

Final thoughts
Love may conquer all. But if weddings aren't part of the equation for more people, such companies may have to hustle to make up for the lost or dwindling revenue from that niche. This could signal tough times ahead for their investors. Who else is likely to get stung from this trend? Share your thoughts in the comments box below.

The Knot and Blue Nile are Motley Fool Rule Breakers choices. Bed Bath & Beyond is a Motley Fool Stock Advisor selection. Try any of our Foolish newsletter services free for 30 days.

Alyce Lomax owns shares of Urban Outfitters. The Fool has a disclosure policy. True to its name, The Motley Fool is made up of a motley assortment of writers and analysts, each with a unique perspective; sometimes we agree, sometimes we disagree, but we all believe in the power of learning from each other through our Foolish community.