The sushi bar makes more money than its one appearance in the movie suggests.
The one time it appears is when it's clearly stated there're no sharks nearby. Normally the occasional shark must eat enough there to keep business going at least until Oscar defeats Don Lino. The movie is set in the same universe as Waterworld
It's not a copy of New York, it's ACTUAL New York after the oceans rose, covering the world.- But how's that explains the fact that characters in this movie are anthropomorphic animals, while humans live on the surface?
Shark Tale is set in the same universe as Zootopia.
The two films have a lot in common: both are set in a world of anthropomorphic animals living in a modern city, full of pop culture references, and feature at least one animal who doesn't like being stereotyped based on their species (Judy the rabbit, who wants to be police officer instead of becoming a carrot farmer). Both movies even have a Godfather-like mob boss in their cast. It's speculated that in Zootopia besides the mammal city there's a bird city, a reptile city and a fish city - maybe the fish city is Reef City from Shark Tale.- A lot of Fridge Horror in that considering that it's implied in Zootopia that polar bears and other predator species eat fish.
