1. Should gay marriage be legalized the next step will be to force churches to change their policy. Before that my children will have to walk through picket lines to their Catholic School.
2. Insurance - As soon as Gay marriage becomes law two things will happen. All non-married relationships will lose insurance (already happening). So the only way to get insurance for a dependent is to marry them.
3. Other "non-traditional" relationships will be run up the flag pole. They will use the same argument - how does it affect you?
4. Schools will be required to teach alternative lifestyles - way til you see the exit of traditional families from the public school system (oh wait - already happening)