Very tragic but fortunately very rare.
There is always safety in numbers and that applies to anchorages as well. It does not guarantee safety but at least it reduces the risk, and it can happen at home. I know of a number of people who avoid going out at night in their own neighborhoods for fear of a mugging. Every paper, every day has horror stories about crime. For all of the bad stories, there are many good ones that you never hear of.
Sometimes you get a surprize and bump into a good samaritan that blows you away. Last winter, my wife and I stopped for a slice of pizza in a little hole in the wall in La Paz. I paid for the pizza, slipped my wallet into the pocket of my baggy shorts, sat down and ate. It was a pretty busy place with people coming and going. We finished, got up and left. About a block down a very busy street, I felt a tug on my shirt and looked down. There was a little boy about 8 years old who held up my wallet and gave it to me. He pointed to the ground and back towards the pizza place, smiled and ran down the street. In the crowd I saw him reach a woman who took his hand. She smiled back at me, I waved, and she disappeared into the crowd. Nothing was touched, american money, mexican pesos, credit cards, etc. I would have been in serious trouble. Never even had a chance to say "Mucho Gracias!"