In my experience, cancelling jobs late means losing percentages not your total spending. Some of the camera crews ive worked with demand 30% of the job cost if cancelled in the last 2 weeks. Basically, 30% would be their profits once all their costs are taken out. In other words, if the show is cancelled, they still make their profits. This 30% has usually been dropped as a deposit.
Same goes for the venue. They might get ( for example ) 1 million from the UFC to run the event, but 700k of that is their own expenses for the night. If the event is cancelled, why would the venue demand 100% considering they also have zero expenses for the evening. In this instance, the UFC would be obliged to pay 300k not 1 million.
So, while I agree the UFC has taken a hit, I highly doubt they are counting the total cost of losing a whole show. eg. 40 million dollar.