I think the problem goes beyond Sand Fleas being hard to find. The beach renourishment program have severely damaged the environment where the Sand Fleas live, to the point that they are no longer there. As a result, the species that prefer to feed on Sand Fleas, most likely , move out of the area in search of a new supply of their preferred food, Sand Fleas. If the fish aren't in the area, the Fish Bites would not be productive, since the fish have relocated.