Robin - what alternative would you have expected to see for 'hate for' in your example?
There seem to me to be two alternatives:
'I would hate the Union Jack to disappear...'
or
'I would hate it if the Union Jack were to disappear...'
The first works well in the written word but isn't easy to say - it wouldn't sound natural in conversation. The second is more natural, but also more convoluted that using 'for'.
Is this use of 'hate for' something new? Sounds perfectly natural to me.