Because of how long it has been taking to recieve these coupon packs & most people are trying to time the coupons with the right sale BB should have them avail. in-store for purchase when you become unlocked. Cross promote the coupons along with the weekly ad & make sure your game reps are aware that way unlocked memberships will increase as a result of the exposure. If a person can make use of the program on day 1 when spending $15 upfront then the chances of them joining increase.
If BB were to sponsor special coupons packs that would also be avail. in-store this would generate instant revenue from the sponsers, increased sales & increase unlocked memberships as well.