So what about the sactioning of gay marriage, regardless of the indirect harm it will inflict on society at large, that won't be immediately evident?
Bingo. Libertarian indifference to homosexuality and gay marriage, “it won’t break my leg,” is indifference to the very fabric of civilization, the family. When that unravels, you have lost it all. Live and let live liberaltarians could care less. Liberaltarians rate only slightly higher than the Democrats, in my view.