I have to agree with you moonlitsub, I think it's a private thing as well with no need to put it in anyone's face. It's not because it shames me, but simply because it's very intimate and personal to me.
I would think the only real reason for 'coming out' to a point would be so you could have your relationship open, in public and I don't mean sexually but the small things, like calling your Master, Master and things like that? Or to bring it more in the open to show that these types of relationships are not 'abusive' and 'demeaning' such as many people think they are?
I'm not sure otherwise