Lately it's basically the only way an exchange can remain in business after a hack. Of course, some will prefer to give up. And of course, in some cases it's inside job too (probably here it wasn't).
But one cannot know for certain what will actually receive in such a situation and there's always a delay.

As said: not your keys, not your coins. One has to be very careful and avoid keeping too much money on exchanges. As I said, one cannot rely that the exchange will reimburse him.