I just wonder what the benefit really is to subsidizing billionaire's and multi-millionaire's private gladiators.

I've always felt there was just too much money (and DoD involvement) in it for "we can take your people to the limits of human capability... purely for entertainment!" to make sense. Do they sell their private advances in sports medicine to defence contractors? Are they some kind of advertisement for super soldiers? If not, what's the gimmick?