Dennis,for my part I side with Dick when collecting cards.I don't care if it is used or a blank.I will update if I get a blank card but it does not matter in my collection.
I know of some collectors who collect one of each so as to their collection I don't know if they value one more than another.
When I sell cards on my monthly list,I price used and blanks of the same card the same.
You know there are some cards you see all the time as blanks and almost never in used.Which is worth more?
Value all comes down to what someone is willing to pay.