Tourists. You literally cannot turn your back on St. Kitts without a monkey sneaking up and stealing your drink. And if you don't have a drink, they will give you one just so they can take it. There are a variety of methods employed by the monkeys in swiping drinks, from the nervous grab and run:
... to the brilliant "knock it over and lick up what's left" tactic:
"Go! Go! Go! Go! Go!"
... to the confident "drink it at the table" method: