Brewer's: Mock-beggar Hall
or Manor. A grand, ostentatious house, where no hospitality is afforded, neither is any charity given.
No times observed, nor charitable lawes, The poor receive their answer from the dawes, Who, in their cawing language, call it plaine Mock-begger Manour, for they come in vaine.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894