Because thieves are idiots.
Fortunately for the thieves, most of the people with the devices are also idiots and don't have the built-in location tracking turned on.
*ROLLS EYES* You've just blamed everything every old fart has blamed on "the kids these days" since the Pyramids were built. Every generation is spoiled, lazy, and morally depraved according to the one before. You can find Graffiti on one a few of the large slabs on the Sphinx to back me up on that. But in actuality, crime overall is down, as long as you ignore that which is systemic and being done by "people who are well and truly fed." We'd talked a long time in this country about the "land of opportunity" and I suppose kids just bought into the idea that they could make a good living. I don't think that's spoiled -- that's just getting played for suckers.
I suspect Bloomberg is not happy with Apple
because his namesake company didn't predict Apple great stock performance.
People get an ugly protective (Otter like) case for your iPhone.
Carriers, quickly disable and erase the stolen iPhone, so they are useless.
Apple, have iTunes disable the IOS and erase the data on stolen iPhones.
Then stolen iPhones are useless, game over!
Both iPod Touch public snatch and run. First was on the subway where a group entered looking for someone holding a device near a door so one could grab it when the door opened and bolt while the rest block for him. Now I never sit by the door if I have device out. The second was on the street, similar, walking home from the subway in brownstone Brooklyn. A group was sitting on a stoop waiting for someone to walk by during a time when the people walking in front and behind were a good enough distance away. Jumped up, jostled, grabbed, set a pick, ran, over in a second.
Neither made me feel any different about NYC. I've lived here for 35 years. You tend to not walk around with your guard up all the time, suspicious of everyone you see, and if you're unlucky that will bite you in the butt. Petty thieves work hard at blending in and they'll wait all day for the timing to be right. I never felt I was any more prone to this kind of thing here than any other city I've lived in.