I cant imagine ever feeling the need to recoup the paltry amount that a second hand drive is worth when I've been finished with it - certainly not one which may have contained sensitive data.
So these stats could also just show that people in the UK are more prone to disposal of their retired drives than resale.
As for the guy with the nude pictures and the contact details - If that was an accident Ill eat my hat.
I used to have a side business recycling second hand machines for resale from the local council recycling centre - the amount of home made porn being produced in central Lancashire and left on discarded PCs is astounding!