Such a loss. But many large buildings suffer the same fate, the running costs for such huge spaces (such as security, heating, cleaning etc) would be astronomical, especially if left empty.
London's equivalent would be the 'people's palaces' such as Ally Pally (Alexandra Palace), very nearly demolished in the 80s after much degradation. They found reuse for the vast rooms as exhibition centres, tv studios and sporting venues, though much is still closed off and decaying.
https://thewestreviewdotcom.files.wordpress.com
www.thestudiotour.com
http://www.londontown.com/LondonEven...agesPage/26435
Back in the heyday:
https://upload.wikimedia.org
Part of the reason why they didn't rebuild Crystal Palace, (and why the local council still objects to any commercial attempts) despite the relatively cheap cost to create and assemble it (the world's first mass produced, industrialised building complex), is the vast size would mean large running costs. The council recently rejected a Chinese consortium as they couldn't prove the legacy of the project would be self sufficient.
http://static.dezeen.com
The same with the large industrial complexes, such as the Bankside and Battersea Power Stations, both partly demolished but saved at the last instant for reuse (as the world's largest modern art museum, and a shopping/ exhibition space respectively).
https://www.pinterest.co.uk/pin/561050066051599994/,
http://pantlingstudio.blogspot.com/2...bine-hall.html
For the country as a whole, nearly 2,000 Country Houses (palatial estates built off the riches of Empire) have been demolished in the 20th Century due to the running costs. It was often a nightmarish fate to be born into such a landed family, through which your every waking hour was spent trying to raise funds for the upkeep of the buildings, and slowly seeing room by room fall into ruin, after the piecemeal selling off of the contents. Entire painting collections, inheritances and heirlooms would go in order to keep up with the heating bills for example.
http://www.lostheritage.org.uk/lh_complete_list.html
www.urbanghostsmedia.com
www.lostheritage.org.uk