Anne, as coming from someone who deals in Obsolete parts and collectables , sellers are motivated by several factors . First, you have the crowd who simply says , hey. it's old , so it has to be rare, read expensive .
You have sellers who actually "READ " the market and actually know what a product will bring .
In any case , just because a product is old , obsolete , or just isn't in use anymore doesn't constitute it as a "Rare or collectable " piece .
Me, I'm cheap and I watch for bargains at shows , auctions , etc ....................