Scams are everywhere for travelers. It's usually pickpockets, but in worse cases, muggers: with knives or even guns, and you really don't have a choice other than give up your possessions. The thing you have to worry about is to be vigilant and well, to be honest, not be an idiot in these situations. There are lots of scams out there, and you can only know what to avoid if you learn the different techniques people use, as there are really a lot of them. Ask fellow travelers online, or on the road you meet, and be vigilant at all times to avoid disaster.