So can "a single bisexual woman who works for a university with excellent spousal benefits" marry her gay male roommate, who is her good friend, in order to provide him with free health insurance? The NYT ethicist Randy Cohen says yes:

People have married for many reasons -- to gain a fortune, accumulate land, forge an international alliance, secure a dynasty, raise children -- and even on account of affection, a marital motive that became widespread rather late in human history with the rise of bourgeois society. ... Marrying to obtain health insurance does not seem, historically at least, the most ignoble reason, particularly where same-sex folks are forbidden to marry for love....

We live in a country where more than 40 million people lack health insurance and thus reliable access to medical care. ... If marriage is his best means to decent medical care, I see no ethical objections to you two kids' tying the knot. Nor would you be deceiving the university if you did.

It requires only marriage, not love. ...

I'm not sure why it matters that these two persons are gay, or why it matters that it is hard to get health insurance and good health care. We wouldn't justify shoplifting based on the discriminatory practices of the store or because the thing stolen was very expensive and necessary. Cohen's point must be that marrying to share spousal benefits is perfectly legitimate whenever two persons go through the legally required steps needed to get married.

If that's okay, unmarried persons with good benefits could charitably find an uninsured cancer patient or other seriously needy person--of the opposite sex, of course--and marry them as a good deed. Or, if economic benefit is acceptable, offer to marry the highest opposite-sex bidder. On Ebay!

If that sounds terrible, consider Shari Motro's op-ed, also in today's Times:

Amid all the heated discussion on both sides of the gay marriage debate, a broader point has somehow gotten lost: why should formally committed couples, straight or gay, enjoy special privileges in the first place?

Married couples can receive thousands of dollars in benefits and discounts unavailable to single Americans, including extra tax breaks, bankruptcy protections and better insurance rates. ...

Research consistently shows that unmarried Americans are on average poorer, sicker and sadder than their married counterparts. Yet they are denied perks given to married couples who, in many cases, neither need nor deserve them. Though gay couples certainly lose out as well, singles of any preference pay a triple price for not finding love: they don't enjoy the solace and support of a life partner; they don't profit from the economies of scale that come from pooling resources with a mate; and they effectively subsidize spousal benefits that they themselves can't take advantage of.

Ending discrimination based on marital status is one way to resolve the current quandry over gay marriage, and it has the added benefit of extricating government (and employers) from a matter many people see as fundamentally religious.