It's EA's illogically named "Project $10" which is responsible for the $15 stone prisoner, the other one is just typical DLC ripping off, you can buy full PSN games for that price!!!!
Anyway, EA's new idea is to give people free stuff to download if they buy new, like the ME 2 Cerberus Network, where you get an extra character (and more in the future) for buying new, and you can get entry to this by $15 otherwise. They plan to stick this in every game this year I think. {I dunno if that will include sports franchises, as I doubt there is much of a problem with people buying them second hand}