They don't want young grade schoolers learning in school that a princess can marry a princess or a prince can marry a prince. Let the children choose how they want to live when they get older and can form their own opinions, not taught in schools where it contradicts what they are taught at home. We are not judging gays or lesbians we just don't want to lose a say in what our children learn in school. If this does not pass with a YES it will be a law to teach this in school.
Also Rob being a bishop would be put in a situation where he can be sued for a hate crime for not marrying a gay or lesbian couple because that is something he does not believe in. Where are his rights to say no?