I meant to say $2 to $5, but also want to point out there are LOTS of places on the beach that charge more than $2... I seem to remember paying around $4 for a Red Stripe at Tree House, and at others...
They also sometimes get funny with the money conversion... I think I remember paying $150 JA for a beer one day, but at the same place when I had $USD it was $2... not something I let bother me on vacation but it happens... And now that it's approx. $110JA per $1 USD it's an even worse deal using US $$$.