Sadly I believe you are right about the workers. We had to threaten our crew not to take in these waters and make sure they had enough food. There are also resorts and tour guides who turn a blind eye to their staff or guests taking out of season or undersized as well. Education and even enforcement of existing laws might help this on going problem. I would hate to see the conch fisheries go the way on abalone.
"Sport harvesting of red abalone is permitted with a California fishing license and an abalone stamp card. New in 2008, the abalone card also comes with a set of 24 tags. Legal-size abalone must be tagged immediately. Abalone may only be taken using breath-hold techniques or shorepicking; scuba diving for abalone is strictly prohibited. Taking of abalone is not permitted south of the mouth of the San Francisco Bay. There is a size minimum of seven inches (178 mm) measured across the shell and a quantity limit of three per day and 24 per year. A person may be in possession of only three abalone at any given time. Abalone may only be taken from April to November, not including July. Transportation of abalone may only legally occur while the abalone is still attached in the shell. Sale of sport-obtained abalone is illegal, including the shell. Only red abalone may be taken; black, white, pink, and flat abalone are protected by law."