Icelandair's Pierorazio said a similar dollars-and-cents argument sold his company on marketing to the gay community.
Pierorazio said gay marriage is a hot topic in European travel markets. On a recent trip to Scandinavia, he talked with tourist boards in Denmark, Finland, Norway, Sweden and Germany. "They were only interested in gay marriage," he said.
Other high-profile businesses, such as the Mayflower Hotel and Bloomingdale's, are equally pragmatic but a bit more circumspect in their approach.
"It's like any other marketing opportunity," said Lisa Collyer, the Mayflower's director of catering. The hotel has been host to several same-sex ceremonies, she said, and participation in the expo is another step into the market.
Donna Hamaker, public relations director at Bloomingdale's at the malls at Tysons Corner and White Flint, agrees that sexuality is not the issue. "These are people looking for something we can provide, whether it's for a wedding, commitment ceremony or housewarming."
Neither she nor Collyer expressed any concern about negative reactions from other customers.
In Baltimore, the gay wedding talk started last summer, said Robert Blount, director of marketing for one of the city's gay papers, Baltimore Gay Life. The paper now has a core group of wedding professionals - gay and straight - who advertise regularly, he said.
David Egan has yet to do a gay wedding, but the owner of Chase Court, a renovated 19th-century Mount Vernon church he rents out for ceremonies and other occasions, has a few booked and is pursuing the gay market.
Concerned about his more traditional clientele, Egan will be at the Washington expo, he said, "to reach out to the gay and lesbian market live and in person."
The Baltimore Area Convention and Visitors Association views the lesbian and gay community as an "emerging market," according to communications director Nancy Hinds. The agency is focused on attracting conferences and tourism in general, she said, but "we know it's an area for growth."
Pitting money against morals, Bill Murray, media director of the conservative Family Research Council in Washington, argues that the profit motive can warp a business' view of "what's best for society."
Sproul of RainbowWeddingNetwork.com thinks revenue potential will eventually soften social resistance. Looking forward to the legalization of same-sex weddings in Massachusetts, scheduled for May 17, she said, "Once the money comes, it's going to change people's outlook."