The computer geeks know where to look.
A user can think that they have hidden or deleted any incriminating evidence. But someone who knows what they are doing can scan a drive for the document or media type off their choice.
Deleted files are still there, so many people do not realize this. Even overwritten files can be recovered to a degree. Cached copies can exist in various nooks and crannies even if the original file is wiped or viewed off of removable media.
I wouldn't be surprised if some less than reputable techies try to collect stuff this way.
(Denny Crane: "I Don't Want To Socialize With A Pinko Liberal Democrat Commie.Say What You Like About Republicans. We Stick To Our Convictions. Even When We Know We're Dead Wrong.")