One would hope that people buy wedding insurance for this. Also, that the hotel would have a legal responsibility to refund those deposits, or that whoever takes over the hotel honours the prior arrangements.
Honestly, this is a risk anyone booking a wedding venue takes, and it shouldn't effect your decision to book up early. If it's a good venue it will be booked far in advance, so if you want a wedding there you have no choice.
#marryxmas wedding report: http://www.hitched.co.uk/chat/forums/t/390321.aspx
Hitched Awards 2013 best hair, 2nd best accessory, 3rd best dress, flowers and venue