Not everyone that buys a bike has one to trade in. Of the ones that do, probobaly some are too effed up to sell in the dealership and get auctioned for parts. Many riders probobly sell their bikes outright on CL or Ebay , Classsifieds or beside the road with a for sale sign so they make more money on the sale. Whenever I sold a bike, I didn't HAVE to sell it, so I didn'T HAVE to take the first offer I got. I could wait for somebody to pay me my price, which I know was a lot more than trade in.
It might be the next thing beyond Ebay , having the dealership take the phone calls and show the bike. It keeps the seller from having to have strangers come to your home and frees up their time . Not a bad concept.