I'm really not against gay marriage.
But I do think a lot of the people for it are hypocrites, because they don't support the rights of other nontraditional unions such as polygamy.
Meh, that's besides the point though I do agree. I support polygamy and even incestual couples as long as they are between consenting adults.
I draw the line at consent (for obvious logical reasons that are easy to arrive at), so bestiality and child marriage are out of the question.
I do think age of consent laws are very flawed though in some instances and should probably be lower which would allow for some minors to "consent" to marriage, however that's a completely separate argument.