Not sure about now, but back in the early 90's, the Topps set was the regular card set that you could put together by buying packs of cards. The traded set, was a much smaller set, with a smaller production run (less of each card out there), was only availiable for purchase as a complete set. Those factors made the cards worth a touch more.
Not sure if it's still that way, but that's how it used to be.
Yes doctor, I am sick.
Sick of those who are spineless.
Sick of those who feel self-entitled.
Sick of those who are hypocrites.
Yes doctor, an army is forming.
Yes doctor, there will be a war.
Yes doctor, there will be blood.....