NEW YORK ( TheStreet) -- The Supreme Court has taken up one of the hot-button issues of our time: the constitutionality of federal prohibitions on same-sex marriage. The case is historic for several reasons, among them that the Obama administration refused to argue in favor of the Defense of Marriage Act ("DoMA"), putting the court in the awkward position of having to evaluate the constitutionality of a federal statute that the executive branch disapproves. Whatever the court decides, though, there are many reasons why the business community should support same-sex marriage. Here are five of them: Weddings are big business. There hasn't been a significant increase in the number of heterosexual couples getting married each year; some studies suggest, in fact, that the number of straight couples tying the knot may actually be on the decline. Adding same-sex couples to the pool of would-be brides and grooms could add millions in new income to the wedding and tourism industries. For example, The Daily Beast estimated in 2011 that same-sex weddings could boost New York City's wedding and tourism revenues by as much as $284 million over three years. That's a whole lot of gowns, tuxedos and wedding cake.
Married people buy houses. According to the Bureau of Labor Statistics' Consumer Expenditure Survey Anthology, married couples can be almost twice as likely as singles to purchase houses, depending on their age and income levels. Allowing same-sex couples to marry would make it easier for them to purchase houses together. Given the importance of the housing industry as a driver of the nation's economy, legalizing same-sex marriage could give industries ranging from new home construction to interior design a significant and welcome bump. Married couples invest. There's nothing like getting married and settling down to inspire consumers to look at their long-term finances. Newlyweds typically buy life insurance -- often for the first time in their lives -- and may be more likely to invest in retirement funds and annuities. For the financial-services industry, same-sex marriage could provide a solid new stream of reliable customers looking for a secure future. Married couples have kids. While it's certainly more common for singles to become parents than it once was, married couples still have the edge when it comes to starting families. Biology no longer precludes same-sex couples from having children, thanks to a range of new medical procedures, and legalizing same-sex marriage would also facilitate adoption by same-sex couples. Middle-income same-sex parents will spend an average of $235,000 per child on everything from formula and diapers to college tuition, which should have companies from Gerber to Disney ( DIS) positively salivating.