Yes, and no! There are more than enough stupid people around who buy top line items on a whim then sell on pretty quick so they can get the next must have trinket. Think about all the muppets that have the latest iphone or wide screen 3D TV that will be outdated or surpased within months meaning another 'upgrade' is required. It all gets paid for on a credit card and gets the purchaser another step closer to financial ruin (reality?).
IMO they are unlikely to be stolen as they come with the chargers and leads, unless they are stolen from a shop. If you are not sure about their legitimacy then move on and don't look back because even after you have paid a chunk of cash for them you will still always have that doubt which will spoil the purchase.