Pick pockets are a hazard wherever you go. So far I have been lucky in the DR, but did get my pocket picked in Venezuela. Two guys were working together in a line waiting to exit a bus. One dropped change on the floor in front of me, and while scrambling about picking up the coins, moving my feet around in the process, the guy behind me picked my pocket while my attention was focused on the guy in front of me.
A couple of precautions that I now routinely take. I carry my wallet in my front pants pocket, not the back pocket where it used to be.
I have a money pouch around the neck that is inside my shirt. My cedula, copy of my passport, credit card and ATM card, and most of my money is in it. If pickpockets should get my wallet out of the front pocket, they won't get much.