There's no responsibility at any level, is the thing. Those people who couldn't fly might get a rebooking and some vouchers sent out to them, but they won't really get made whole. The airport knows they won't really be on the hook, so they don't demand real responsibility from their vendors, and so on.
In the grand scheme of things, being able to fly around the globe at these prices is a pretty good deal, even with these rare events taken into account. It's not like the planes fell out of the sky. If you must must definitely be somewhere at a time, plan to arrive one or two days earlier.
