If I shucked them though, and put them in ice in the fridge, how would I be able to tell if they were alive? Could I have shucked them and cleaned them up at the clean station and iced them to cook for later, since I had had crushed them with the shovel? They did squirm after being squished so they were alive... The people at the shore shucked them, cut off their necks, removed the foot, and separated them into two containers, so I don't know if they were really alive by that point. The "dead" ones I had are saved for crab bait so at least I won't be really wasting them. 
With the speed of the water, I don't know if I could fish for the crabs out there! Maybe I'll have to try to try said calm water crab hunting some time. It took darn near the entire 100 foot rope to get the cage to the bottom, and in some cases, we had to re lower the cage or net with a few large rocks because the current caused them to just stay kind of floating.  It was a good   50 feet of  water straight down under the docks or so I am told. Might have to try a calmer day to go crabbing.