Recently I was walking on Santa Fe near Callao. An ELDERLY couple was sitting at an outside table next to the curb. The man had a guide book (in English) in his hands and his trifold wallet was open on the table in front of him. I could easily see the credit cards in the slots and his driver's license in the plastic window. It would only have taken an instant for someone to grab it and run (with little chance of being caught.) Of course I stopped and warned him to get his wallet off the table and not even allow others to see him taking money out of it, adding it is better not to even carry it with him here.
Then I noticed that his wife (who was sitting with her back to the curb) had her bag hung over the back of her chair. It was a wonderful target to anyone passing on a moto or a bike. They were shocked that such crime could occur in such a nice area of BA with so many people around, but they were happy not to have lost their valuables.
Yesterday, as I was walking to the Dicso supermarket on Uriburu, another (obviously) American in his 70's was waiting for cars to pass before crossing the street. Actually, he was jaywalking and leaning out from between the parked cars with a high end Sony digital camera slung around his neck. He had no idea what a great target he made for a thief on a moto. (If you've been here a while you know how they weave in and out of traffic and along any space between the cars and the curb.) Imagine the physical harm that could be inflicted by someone grabbing the camera strap without stopping. If the strap being jerked didn't break the neck, being slammed to the pavement in traffic or just into a parked car could prove fatal, especially to an elderly individual.
The best camera to use here is one small enough to fit in a pocket.
Check out the "avoid becoming a victim of crime" thread for more info.
You may not ever have a problem like these, but you can still get ripped off here...and for a lot more than a computer, camera, or some cash you had in your pocket.
Especially if you are dealing with a lawyer, architect, or customs broker.
Just to name a few.