Is there a restaurant that serves all you can eat crab legs?
If you do find a place that has AYCE, it will probably be cheaper to go over the bridge and buy them at Publix. Crab legs are not local to Florida. They are from Alaska, frozen, and flown in.
If you don't mind cooking we found crab legs snow and king crab along with lobster claws at Joe Patties much cheaper than Publix.