Here's an idea! You could do it kind of like what the big motorcycle groups call a "Poker Run". I believe they supply a map and travel to various places where you pick up a playing card. The one that comes back with the best hand wins. That version is in no way dependant on finish times and is more about a bunch of guys getting to ride through some scenic places and still give them something to talk about.

Our version could place cards at businesses that are close to beaches in different directions and have the competitors travel to a different far away business on each day to collect their cards (and the business would get some sponsorship opportunity and/or could help establish a landing spot on the beach). The card is the proof that they got to the spot in question. In the end I would imagine that the overall low CT would be most important but maybe there could be a second prize...say a big raffle item or a collection of items from the sponsoring businesses...that would go to the team with the best hand.

Some work would need to be done with the local municipalities but the business could prepare a landing/launching area on the beach with a table to hand out cards (and the competitors have a map supplied and/or GPS coordinates). The sponsor would benefit by putting a banner up in the cordoned off landing area and drawing attention as the boats come in and out. They could probably even supply the help to man the table and perhaps even to re-launch boats as long as one race official were in place to make sure things were done properly. That would be a lot of fun!