Scanning what card? You go to a Gamestop, open the box, pull out the sheet with the code on it, snap a pic with a camera phone, go home, look at it, and put it in. I went and did this as I had some games I owned previously and didn't enter in for prorated points. Yah, not nice, but it worked.
You see the problem is you're talking about not the Club Nintendo points, you're talking about Wii/DSi 'Nintendo Points' and yah those are on a card. Next time be correct and specific when asking a question.