We did have a discussion about this a while back. Here in the US, all the PSR2000 boxes say "power supply included in box". When you bought one on EBAY, where did it come from? A different country? If it was a private party, this person didn't get it from the USA.
Next, survival kits are included when dealers purchase keyboards in certain required quantity. I, as a dealer, never charge for the survival kit which includes tha AC adapter, headphones, pedal and two year extended warranty when I sell a keyboard. Even the lowest price keyboards and the digital drums include these accessories at no charge. Some dealers might charge for these accessories, which is their choice, but I see it as a way of giving something extra to my customers that you won't get from the mass market stores that compete with music stores.
George Kaye
Kaye's Music Scene
Reseda, California