That $30 price you are putting on a young rookie signature card is a conditioned price that you have gotten used to from Select's Signature cards. We were also conditioned to expect parallel cards are worth approx $1 and when ESP limted came out last year everyone said wtf, won't pay that much for a parallel. Sellers will structure the price so that they can recoup costs regardless. Yes, the ESP parallels do now get bought anywhere between $6-$10ea. Yes people pay that price. It's just the way the market works.
It works the other way too, you tell an NBA collector that you just payed $30 for a next to no-name rookie auto #/300 and they would laugh. You can pick up autos of NBA Stars numbered less than 50 for $5.