I thought a main goal of the registry was to show-off collections and encourage friendly competition?
I notice there are a lot of "obscured" sets, including category winners. I believe that if a collector wishes to hide his or her set or their company's set, fine: do so.
But if they want to hide them, why are they also eligible to "win?" If they don't want to share, then fine - unregister the sets and keep them out of the sight and minds of others.
Just my opinion.