There's a compelling argument that government should get out of the marriage business altogether and give gay and straight couples "civil unions" alike.

If, as some people claim, marriage is a sacred institution, why is the state involved at all? Who would be OK with having to go to the courthouse to get a baptism license?

For people who object, choosing to attend a church that doesn't perform gay marriages will be no different from choosing a church that wouldn't perform anything else. Churches aren't regulated. (note: this is almost a "let the market decide" argument)

I do not, however, support the rights of fellating bats to have civil unions, because bats are creepy.