Get breakfast for free this week at Walgreens! Kellogg’s Breakfast To Go single shakes are on sale for $1.49. Buy one and earn a $1.49 Register Reward. A Register Reward is a coupon that prints at checkout. It can be used as store credit on a future Walgreens shopping trip. Also, remember that you can only earn one Register Reward per offer per transaction. Ask your store ahead of time if they’ll allow more than one transaction. My store had two flavors: chocolate and vanilla.