[bkst]

>If they love the book and not the content, why do they care if the content is available.

They want to have something that others can't have.

>Wouldn't you rather own the only copy of a famous atlas, then an obscure one?

Some would, but there are plenty who prefer the obscurity. Most aristocrats are more interested in impressing their friends and immediate circle with off-beat style than in starting a popular museum or being seen as gaudy. Obscurity is hip--and sometimes it can even be affordable.