Majority Rule? No, Motivated Rule

People are more or less the same everywhere. When it comes to denying the rights of minorities people are generally in favor of it. Or at least the people who are vocal and will turn out to vote against their fellow man are in favor of it. The enthusiasm to protect a group of people that are not your own is generally lukewarm. As long as a person feels this has nothing to do with their own rights, that protection of minorities as protection of ones own rights is a distant abstract, then they won't be bothered to actually do something in most cases.

Hence why on the one had a measure aimed at illegal immigrants driving in Denver went down to a flaming defeat by 7 to 3. It would have impounded the car of anyone caught driving without a license and put in place a $2500 bond to get it back. There were some bits of cut out to allow licensed drivers less trouble, but it would still have cost the city a lot of money to enforce and taken the police away from other activities. But primarily it was the fear, "What if I'm pulled over and I don't have a license?" that motivated people rather than any sympathy for unlicensed illegals. My own motivation was pretty much selfish.

On the other hand whether it is the Swiss banning minarets or American voters banning gay marriage the majority does not see a way that their own interests are being gored and so they let the vocal people in favor of hurting the minority have their way. There is a lukewarm majority in favor of abstract fairness and a level playing field, but these people are not very motivated to do something about it. Not until or unless they can imagine themselves needing or wanting something. Hence why Civil Unions, measures with provisions for couples straight or gay, can succeed narrowly.