We have no idea on the actual corporate costs, leases on office buildings (which they seem to be putting all over the world inorder to grow the sport) employees to work in those building, travel costs for promotion, insurance costs on every single fighter, not to mention the costs of actually producing an event.
Ive heard that the ppv distributor takes 50% right off the top (I could very well be wrong though), the cost to rent out the venue, tv production staff, setup/teardown staff, etc.
If you assume the UFC has maybe, 1000 employees worlwide, each making $40,000 on average (general admins probably less and tv production/setup crews significantly more) you're looking at $40,000,000 for staff alone each year. And that doesn't include fighter salaries.
I'd love to see fighters paid more, but until we know EXACTLY what kind of profits the UFC sees people should really stop assuming DW and the Fertitas are milking the fighters and bleeding them dry.