I have been to many Best Buys in the Pacific Northwest. Only in one of them did I ever find these cards. I was told that each store has the choice of them being a regularly stocked item, which means, if you abuse it, they will stop carrying the cards. It's my only guess why I've only ever seen one card total.
Now that I'm in LA though, I'm definitely going to be looking around to see if any Best Buys around here have the cards, because 1/4 off of VC games is freaking sweet.