I used to think that people wouldn't do these things, but some do them regularly and unapologetically.
I once caught a car technician from a reputable dealership's service taking my car out for personal chores, as the guy did not even unplug my dashcam. I had a rude awakening when I realized these things aren't just urban myths but that they do happen. Some people have no qualms about taking advantage of our unattended things. Of course, this is an anecdote with a sample size of 1, and I can't speak about how often these things happen.
But I'm honestly not that surprised to read section 5 in this paper. Not even surprised to see that there was no attempt to cover tracks on most laptops.
A mechanic taking a car for a ride is at least plausibly productive; the mechanic tests the car out to make sure it's running well, no weird noises/etc. Of course if you just brought the car in for an oil change and not asking them to investigate a weird intermittent noise, I can see why you'd be upset.
During the so-called "Fappening" one of the rumours about the source of the photos was a group of Geek Squad type tech support employees that were trading the photos that they pulled off of devices in their care. According to that theory the ages of the photos were mixed because that group had mostly kept them to themelves until the large leak of the whole corpus.
