[tomkarlo]

Pickpockets depend on the fact that you won't realize what they've done until they're long gone. What you're talking about is more like the old 1980's-era-New York-type chain / purse grab, and that doesn't seem to happen as often any more because it's so blatant.

[wittrock]

It happens all the time, actually. Michael Bloomberg has attributed the rise in New York's crime rate recently to a rise in the snatch-and-grab thefts of Apple products. [1]

[1]: http://cityroom.blogs.nytimes.com/2012/12/28/crime-is-up-and...

[bsimpson]

It depends. They also rely on the element of surprise. Everyone I know who's been mugged or seen one happen on public transit has had something grabbed right as the doors are closing, so the thief slips away before you have time to squeeze through the crowd to run after.

[tomkarlo]

When someone does that, everyone on the subway car sees it. When someone gets pick-pocketed, nobody sees it. So there's a major sampling bias.

That said, I've also seen some NYT articles saying the true "pick pocket artists" are a dying breed, because younger criminals don't want to spend the time learning it and the potential take from a wallet has gone down as folks carry less cash.