Nothing is stopping a few of you from going old school. Just race the boats up the course the way it all began. You don't need anything but a few commited boats. Agree on the stopping points and keep your own time. This is how most of these races began.
True, but things aren't quite like they used to be. On many of the Florida Beaches, if a catamaran shows up on a beach overnight without a permit it gets ticketed or worse. Organizers of late spend weeks traveling up and down the coast to get the required permits and every beach / municipality has their own rules. For instance a quick search shows Pompano beach here:
Rules: Boogie boarding is allowed everywhere on the beach, but surfing is only allowed north of the pier. Wrist or ankle leashes are mandatory. Catamarans and sailboards can be launched only at Northeast 16th Street and must stay 200 yards off the public beach. (Boat and jet ski launching is available at Alsdorf Park at Northeast 14th Street and the Intracoastal Waterway).
Other places like St Augustine deem any catamaran left overnight on the beach as "trash" and can come pick it up and chunk it with no notice. It's hard to tell how closely these rules are policed but I'm a little hesitant to risk my racing machine to this kind of end.