Honest question: where in Negril do you have to pay in $US, and they don't accept $JA?
Are you speaking specifically about having to book your hotel in $US? If so, it's more about the fact that the American dollar is stable right now, while Jamaican dollar is not. If they listed in $JA they would have to adjust the prices like every week. Plus it makes it easier for prospective customers to know how much it's gonna cost to stay there.