I think the whole thing here is that most people don't go to clubs or clubbing because of music and dancing anymore. A lot of the youth goes to get plastered, to check people out, to 'hook up', to hit on and get hit on lol. I think this is why some people have a problem with their significant other going out clubbing. But I do agree with you, there are those who go for the music and dancing, which would be the reason why I would go.
As Sip had said "If clubbing is used as a release and not as a substitute for something that is lacking in the relationship, I don't see a problem with it," I totally agree with him.