"Residents" are a minor portion of the "population" of South Walton County. I don't know the exact figures, but it certainly feels like the amount of people is approximately ten times more people in July than February. If the county can craft an ordinance that defines the customary use portion of the beach as, perhaps, "half the distance from mean high tide line to primary dune line, or first seaward structure", then it would seem to be a workable plan, if our visitors can be educated to comply with this.
I just came up with this formula, and would certainly want to hear other ideas.