You win a free tour or boat ride
The scammers will approach you and tell you that you win a free boat ride. So you need to follow them and go to the office so you can claim your prize. But this is just a scheme, when you go there they will try to sell you a tour and there is no way you gonna get your free boat ride. So to avoid this just ignore these guys. Pretend you are mute. These guys will make you waste a lot of time if you engage in conversation and follow them to the office.