This is part of what BB is calling customer centricity. Right now, some locations have switched to this set-up with all BB's being this way by 2008. The stores that accept and sell used games are called "Ray" stores. These stores are supposed to cater more towarads blue collar, middle class customers. They accept trades on alot of electronics because "Ray" spends his money on quite a few electronics for his family, but hates to see newer, better things coming out so fast and wants to get some return value for his current stuff.
BB also has "Buzz" stores (the 20-35 guy crowd that has to have the newest and best),"Barry" (The middle aged version of Buzz with much more $$ to spend), and then there's "Jill" (the soccer mom who hates shopping for electronics, but her family likes them and she controls the checkbook). A BB that has been given its segment will still carry the same DVDs, VGs, iPods, but will have different stuff depending on the customer they are supposed to have more of and making each BB a little bit different.