I like them as souvenirs of places I've played. I have lots of cards with names of unknown players, and some that haven't been imprinted, but I long ago decided I will never get all the designs, so the personalized ones mean most to me.

From what I've seen in eBay auctions, the no-name cards seem to bring a buck or two more. I would guess there are collectors who only want cards never imprinted for a player.