I can see it now: Picture this, you take an escalator down a giant plexi-glass tube to the dining room which is actually submerged under twenty feet of salt water. Crabs feed on the floor, fish swim around. There are decorative ones, and then there are your stock fish for dinner. Your waiter brings you a menu of the variety of live fish and their preparation, and via com system, a diver already in the tank is sent to catch your live prey. Maybe he just picks out a great looking crab from the aquarium floor, maybe he has to spear a fish, but the fun is watching the chase. Think of it like those restaurants where they do live jousting, but MORE AWESOME because it is underwater and actual hunting is involved.
Now I just need to find some extremely wealthy eccentric willing to fund such a folly. We could be on the front page of Travel and Leisure...or GQ...or Highlights or something.
But in the meantime, until I open my underwater restaurant, you can purchase live fish, or fish heads at ABC Seafood all of the time.
Hell, they even had live crawfish! Sure you could set up a trap in almost any stream outside of town and get just as many for free, but if you don't want to work or spend a day in the wood, this is your place.
My folks and I got lobster. Two of them, in fact, for a really good price.