This wouldn't have happened 10, or even 5 years ago. The availability of cheap, poratble high capacity storage media has resulted in a much more lax attitude to data security. Added to which, many of the contractors involved will not have the same security mindset as a member of the Forces or a career Civil Servant.
Obviously, you can get a lot more info on a 160Gb poratble hard drive than you could ever get on a 1mb floppy, but people tended to take more care of those, and USB memory sticks are so common these days. (I have one that has an 8Gb capacity) so the numbers invoved are much higher - easier to drop the whole database onto the storage to test off site than to take a proper, redacted set of test data.