When I worked at Citibank's IT department I once was told that every time they upgraded computers from a department, the old machines were sent to a warehouse and the hard disk completely destroyed, with a drill right in the middle. That was standard protocol, even for low level employees that most likely didn't store anything confidential.
Heck, I have 2 old cellphones in a drawer in my bedroom, I don't even know if they still work, why would I sell them, for how much? No one buys deprecated cell phones. I'm planing to move next year so I'm already in the process of throwing out old stuff, I'm gonna throw both of those old cellphones in a trash bin.
Now, think about a celebrity that can have all the new mobiles in the blink of an eye, for free, every what, 6 months or so? What would I do with the old device? Give to a nephew? Give to the kids to play with it? If this goes to wrong hands it can be a pain in the ass, I would destroy it too.
I'm not saying that that was what happened, just that it can be extremely normal in the celebrity world to have some sort of protocol regarding confidentiality, things that we don't even think about.
