What many people need to watch for and even the most experienced travelers have been victim to are pickpockets. Many of these people can get inside your pockets jacket or purse without you even knowing it.
One scam that works really well on tourists is using kids to either distract tourists or the kids themselves are pickpockets. I was almost a victim of these when a group of children came around an outdoor Cafe in Spain and were chasing each other and looked just to be "kids" playing. One boy, approximately 7 or 8, bumped into me and I felt his little hand going into my pocket. I caught him and they all ran. Luckily I had an amateur. There are other "kids" who are much less clumsy. It's a reason that many locals never carry anything of value in their outside pockets.
I have now "heard" that kids on the islands are doing the same thing. They rush the tourists begging for money or treats and then pick their pockets. It's always why it irks to see people giving the kids candy and coins. One time I even saw a woman, from the ship, with a bag of candy throwing handfuls of it and the kids were fighting over the candy on the ground. Now that's "The Ugly American" syndrome.