Hilton has 173k employees. So a ceo who can get minimal amounts more out of them or cut the cost of them even slightly is worth a fortune.
I think this is the real driving force behind the ceo pay numbers we've seen: more big companies where a single ceo or a small top-team have huge leverage.
I'm not making a moral arguement. Just a practical/Economic one. I think "leverage" is a better concept here than "responsibility" (which carries moral implications...)