That was my first reaction, but I think that's because I somehow equate seafood with fish and fish is really hard to serve in a buffet without getting dried out. But of course seafood is a lot more than fish, as the OP points out. I do worry about sushi in a buffet - how fresh is the fish in a buffet.

But Harrah's Tahoe has a really good buffet - not specifically seafood - but they do have lots of sushi, often crab legs, and other non-fish seafood items (as well as fish). And a spectacular view.