Tazzer,
Belize is an ex-British colony and, as such, has somewhat conservative laws. I don't know if it's technically legal to walk the sand with a beer in your hand, but I've done it a lot without any problems at all. The local stores will usually offer to open your beer for you as soon as you buy it, too. However, it's not a bad idea to get one of those neoprene beer "coozies" to keep your suds cold anyway. Remember the usual disclaimers: Your mileage may vary. Close cover before striking. And my personal favorite, keep away from children.