You do not need a card at Walgreen's, but you do need one at CVS. Each store has its own policies on what you can use the rewards on. At either, you can't use them on gcs, alcohol, tobacco, lotto tickets, etc. At Walgreens, you can't "roll" them, so if you buy Herbal Essences and get a $2RR, you can't use that $2RR to buy another Herbal Essences. At CVS, if the reward limit is more than 1, you can roll them. CVS extra care bucks are typically good for 30 days after printing - not sure about Wags' RRs.
I don't shop at Wags because it's too far away. However, from what I know about their coupon policy, CVS seems easier to figure out. Check out coupon forums like hot coupon world, a full cup, or we use coupons to see some faqs about both stores and how to work the rewards programs.
