Crabby's in Mays Landing. I read a review somewhere online that suggested they have all you can eat blue claw during the week but they don't have a website to confirm. It is very small and low-key - paper on the tables, just beer and crabs. I would just call first about the all you can eat.
Cap'N Cat Clam Bar in Franklinville has great crabs, but there are no sides. The menu didn't say blue crab, and it's not all you can eat - but the portions are big. You can actually BYO sides (salad/bread), however, they do have a full service bar.
* Menu - Franklinville, New Jersey - Cap'N Cat Clam Bar
Now I'm hungry for crab!