>>33819011OP here. The cards are given away for free at each retail location for a set period of time. The purpose of the code cards is to give a reason for a Pokémon-oriented consumer visit the store. When a consumer has traveled to the store, they are more likely to also purchase something while they're there. Essentially, it incentivizes a store visit.
To my knowledge, Target hasn't done any store exclusive codes prior to this Charizard. They weren't really promoted much, either. During the two weeks of this event, at least while I was working, I had only 2 people ask me for code cards. So we were left with a lot of them.
