If you get to Cape May early enough, they will usually take walk-ins without a fuss when they first open. I think they open for dinner at 5:30 pm. We've done this in the past and even with a large group, we never had to wait for more than 10 mins (they seat ADRs first, then the walk-ins.) I can't remember if they have crab legs but there will be plenty of clams, mussles, and shrimp.