Short answer: Yes. Yes you should.
Long answer: Why wouldn't you buy a Roatan Marine Park yearly bracelet? They're only $10 and all the proceeds go towards the running of the park. The Roatan Marine Park is a non-profit organization that installs all the dive moorings, runs patrols to patrol the local wildlife and works with the local community to move us towards a conservation oriented island.
So if your boat ties up to a mooring, or you see a turtle or lobster or conch, or notice how the mangroves are starting to grow back...then of course you should support the Roatan Marine Park. The bracelets are only $10 and all the proceeds go directly into helping the park continue its good work. The park is one of the best run that we've seen, and we believe it has a lot to do with the fact that it's run by a non-profit, non-governmental organization full of passionate people, and we'd like to keep supporting it.
Do your part, support the park!