I don't know enough to speak intelligently about this specific issue between the two ferry companies, but in my travels around Belize over the past 20 years I've often noted the typical reaction by Belize businesses to declines on the top or bottom lines is to raise prices, rather than to try to operate more efficiently or to reduce prices to bring in more business. "Hey, we're not making money at $10 a widget, so let's raise our prices to $20 a widget and see what happens."
The result in the end is significantly higher prices in Belize compared with every other country in the region for just about everything.
Of course, it's not totally about competitive approaches as much has to do with Belize's market size, low population densities, government protection of monopolies, government over-taxation and over-regulation, and so on, but I must say it's damn nice to see price competition for a change.