The paltry sum contributed by the taxpayer to BBMF is nothing compared to the advantage the flight gains by being part of the Royal Air Force and operating under military release to service. If it was civilian operated the aircraft would operated under CAA rules - what expensive and non-authentic modifications would the aircraft need to comply with modern CAA standards? The word VULCAN comes to mind.
Moreover, what would happen if the flight needed industry support to overcome a show-stopping issue with one of these precious aircraft. Would the support currently enjoyed by the flight be offered to a civilian company? I doubt it.
The Royal Air Force has a glorious history and it is all to do with aircraft - comparisons with the RN historic flight are simply not relevant - the RN operates mostly ships I believe. The BBMF aircraft remind us of the sacrifices made in the air and on the ground, particularly in the Battle of Britain.
May I remind those who would readily commit the BBMF to the past that the motto of the flight is 'Lest we forget'. Best we do not.