Because usually "lots" include lots of commons or Basic energy cards, which people don't really need. It's a rare find to have someone looking for many cards from the early sets(*), most would be looking for 1 or 2 cards to complete their set(s).
(*) Except if you had 1st ed. Base or Shadowless cards. People would go for a Lot made up of those cards. You will on occasion find someone interested in a Lot of 1st ed. Jungle or evern 1st ed. Fossil but those are few and far between.
"We are not purposely trying to mess with your minds."
Indentifier of the Magby Rule.
Diamond & Pearl H/W
You'd be crazy not to attend the New England Regional Championship.