Hi Danielson
Why Why Why??? that is the question? I have no idea why, but they certainly are wasting $10 a year per domain keeping them
It doesnt really matter what their thoughts are when registering these names are, the bottom line is there are no sales with names like these, so personally I dont care why they registered them, and as a seller yourself, I wouldn't worry about it. Check the registration dates and most are after 2009 and some just last year so doesnt that make you think why were they recently registered, if there was any value in them, they would have been snapped up years ago.
Most of the modification dates havent changed either so you can be sure they havent sold
Just go and check the sites, most are just crappy old parked sites with "for sale" links, if they had any value, some would at least be developed
Hope that helps