Yes, a pinot gris or riesling is a safe call with crab, though a chardonnay is the safest. But what about those prefer red wines? Yes, that means ignoring the rules, but if a red wine is preferred then a pinot noir would be a nice bet.

Rules are made for those that want to follow. You know what kind of wine goes with the crab you like, and if you do not then experiment. Let your taste buds rule!