The best negotiators are vast repositories of caginess, steeped in guile and cloaked in sly wariness. So too are the best mothers and fathers; their progeny are full of cunning and near-limitless energy and must be supressed or at least protected from the perils of the world to a degree.

Also refers to a higher class of strip club...replete with cages for the pretty girls to wriggle within and remain protected from unwelcome pawing and groping.