I've been in the position of the guests who asked for their money back....
One of my mates cancelled her (ludicrously extravagant, at least to us) wedding, at three days' notice. As it happened, the wedding was postponed - bridegroom had cold feet.
We'd paid,not just for flights, hotels, etc., but for two family banquets at her pricy hotel, at £45pp each per meal.
While I was extremely hacked off, not in a million years did anyone consider asking her for a cheque.
But I was a bit taken aback when a great many people - including the bride's parents - went on the 'holiday' anyway, leaving the lady herself slumped in gloom in the UK. Us mates dragged her out to lunch on the day it should have been, but still.
Oh, and when the couple finally tied the knot they went for a Waitrose buffet in their front room. I think they realised no one would be up for spending another £800 each.