When you are traveling, you will occasionally get ripped off.
You don't know the customs. You have too little context for a solid foundation of trust. You have nothing to compare to. You are stepping into the unknown, and some people will take advantage of that.
A small betrayal is not something to be upset about.
It's part of a time-honored tradition. The world works this way.
It's the cost of traveling through this world without worries.
It's worth every penny. Pay it gladly.