The Phoenix Zoo has been home to a couple of Ringling Brothers elephants for several years now, including one that killed a keeper while at the farm in Florida. They also had a brother and sister (only the sister now) lions that were part of the pet trade and had been born in an apartment in Pennsylvania. They wouldn't breed them (obviously not to each other) to other lions because their background is not known.
Lions, Tigers and Bears in California is about to get 3 tigers that were part of a traveling circus. They haven't said which one, but the point is, yes, they're going to sanctuaries. I don't know if they'll go to regular zoos, though.