Man on bended knee, gazing adoringly at beloved: “Darling, would you walk life’s path with me, sharing job benefits and pension funds? You know I’ve always wanted to file jointly. What do you say – let’s qualify for sick leave together!”

People get married for many interesting reasons, but health insurance? That apparently is the belief behind a conservative pro-marriage group’s protest of a Portland ordinance providing domestic partner benefits to unmarried couples, whether heterosexual or gay. But if anything, the measure reduces the mere economic incentive for heterosexuals to marry so these couples can concentrate more on love, honor, respect and the other fundamentals of matrimony that the Center for Marriage Law should want to promote.

The center, based in Washington, D.C., earlier this week filed suit on behalf of 11 Maine couples recruited from local churches to challenge Portland’s ordinance, which has been in effect since 2001. The suit, filed in Cumberland County Superior Court, alleges that the city’s ordinance conflicts with a state law that defines marriage as the union of a man and a woman. Portland’s ordinance, similar versions of which were also adopted in more than two dozen other Maine communities, extends the legal rights and benefits of marriage to domestic partners, thereby equating same-sex couples with traditional married couples, says the group’s lawyer, Vincent McCarthy.

If the availability of health insurance for single people discourages marriage, woe is Maine when the governor’s Dirigo universal-access plan is in place. The romantic in us hopes that couples get married because they want to spend their lives together, celebrating life’s joys and helping each other through the rough spots. Other couples may want the same thing but choose not go through the legal and social ceremony of a wedding. If they are gay, of course, they are barred from doing so.

Domestic partner benefits, which are offered by communities as diverse as Eddington and Camden, Baileyville and Scarborough, do not confer many of the other financial benefits of marriage. Unmarried couples cannot claim one another on their tax returns or collect retirement benefits for a deceased partner, for example. So, these local ordinances aren’t close to setting one on the slippery slope of undermining marriage. More important legally, neither do they conflict with state law.

The idea that domestic partner benefits are so enticing that they encourage significant numbers of people to live together but not marry has yet to be demonstrated. Some communities that have offered the benefits for several years have found that no employees have signed up for them, others have a 1 or 2 percent participation rate.

To qualify for the most common municipal plan, which is administered by the Maine Municipal Association, partners must sign an affidavit that they are in fact a couple that shares financial and other obligations. Just by signing up, couples are reaffirming their commitment.

Affordable health care is one of Maine’s most pressing needs as the costs of covering the uninsured are often passed on to the insured in the form of higher premiums. So, anything that allows more people to be covered, as do the domestic partner benefits also offered by the state, the University of Maine System, and many private employers including L.L. Bean and Maine Medical Center, should be applauded, not challenged on shaky legal and moral grounds.