Politics: gay marriage save us all money?

At worst, a nice dream.

San Francisco City Attorney Dennis Herrerra argues in favor of same sex marriage that the unions could add 10-20 million to the city's budget:

Most of the estimated savings would come from having lower public health costs, including visits to city hospitals and health clinics. That's because same-sex couples are much more likely to be uninsured than married couples, according to recent studies by the U.S. Census Bureau and the National Center for Health Statistics. If same-sex couples were allowed to marry, Harrington reasoned, more of them would qualify for spousal health benefits. The remaining increase to the city budget would come from additional fees for city services, sales tax revenues from the expected surge in weddings and honeymoon visits, and hotel tax revenues from nonresident weddings.

I'll remain pleasantly skeptical, but I'd like to see some number crunching on this stuff to see if it could be true.