>Mark,
>whilst I agree with your sentiments, if trying to book an event of this size in the UK most hotels would want a substantial deposit for the whole group booking not on an individual basis, which really amounts to the same thing
>Regards

Upon further consideration, I have concluded this is nothing short of loan sharking.

I work for the Federal Government here, and we have arranged many large national and regional conferences and had hotels gleefully set aside blocks of rooms at special rates without extorting interest-free deposits from the travellers.