Re: Crab Pots
I could be wrong about this but I think the advantage to keeping them live is to ensure you don't cook a bad one. We don't cook a crab that doesn't appear healthy (frisky.) If you keep them cool, moist and right side up they will keep for days out of water. By moist I mean covered with a wet fabric such as burlap that will allow air to flow through, not under water.
I live in Florida but learned to catch/eat crabs in the Chesapeake area, so I have to plug steaming as the best method of cooking - plenty of videos out there. One note though if you opt to ice them down before cooking you will need to increase cooking time to compensate for the cold crabs. You don't want mushy meat and too long in the heat dries them out.
Enjoy! Oh yeah, don't eat the gills.