I think some, but not nearly all, of the garbage in the water around the Bay Islands can be blamed on the islanders. Almost 20 years ago we rented a kayak at the Coral View resort in Utila and paddled from there on the south side through the mangrove-lined canal that runs to Rock Harbor on the north side. At Rock Harbor we were absolutely stunned at how much plastic garbage was littering the beach. When we got back to the resort and returned the kayak we commented on it and the staff said that a full beach cleanup had been done there literally the day before - what we saw that day was the result of one day of winds out of the north. Utila's population at the time I think was somewhere around 3,000 and they all lived on the south side, so I can't see any way it was their garbage on the north shore the next day. I also can't imagine how much garbage washes up on Utila's north shore these days if it was that bad twenty years ago...
For the OP, it takes some truly, truly awful weather for Roatan dive shops to not take customers out. We were just diving in Roatan in early December, based in West Bay - after Sara and also after a strong norther and during a light one that resulted in strong winds out of the north, some nasty rain, heavy seas (by Roatan standards, probably light to medium by Pacific Northwest standards
) and poor visibility. As a result our dives were split almost 50/50 between SW (Mary's Place was the farthest east we went on the south side) and NW (El Aguila wreck was the farthest east we went on the west side). Dives were all excellent despite the poor visibility, and our drift dive at the West End Wall was the fishiest dive I have ever done - among other things a couple of turtles, a pair of eagle rays, several porcupine fish, a green moray eel, Atlantic Spadefish and one of the largest schools of Creole Wrasse I have ever seen. Granted I have limited experience (certified three years ago), but that dive was epic for me. I agree with gdog above - sometimes you just gotta be a the right place at the right time.
@Gdog I am curious - how many days of diving did you lose around that slow moving Tropical Storm Sara?