Do some Wii VC games not get coins? I bought Paper Mario a few weeks go and no survey for it has shown up, but Zelda: Majora's Mask, which I bought the same day, has. Both games show up on the "Products" tab, just no survey for Paper Mario.
All VC and WiiWare games released before a certain date don't qualify for coins. I don't remember what the date is, though.