I cannot imagine trying to teach someone Cartwheel while checking them out. When there's a Cartwheel offer for clothing, I need about 5 minutes to teach a person how to use Cartwheel. What it is, why you need the Target app, how to navigate the Target app to get to Cartwheel offers, the difference between category search and barcode search, how to see the alternate offers, how exclusive offers work, how to see your list and how many offers you can have on your list, how to get to your barcode, how to find the in store Target coupons and pointing out they have different barcodes, 6 uses per day, stacking Cartwheel and a Target coupon and a manufacturers coupon. How are the lines supposed to keep moving quickly when you are "educating guests"?
The thing is, you could be playing with someone's rent money. Someone buys something and there's something wrong with the transaction. We'll say $25 and it should have been $20. You do a return and rebuy, well they are now missing $45 from their account for 3 business days. 3 banking business days rather, if Monday is some relatively obscure holiday that banks recognize, well that's another day. What if someone needed $15 of that for enough food to make it to payday or gas or a doctor's appointment? Oops, you can't buy your kid milk or antibiotics because we are having a coupon fraud problem. What if someone had a check out that has the money in the account for it, but the return/rebuy is tying up some of the money which means the check will bounce even though the money is there. Oops, you have a $35 overdraft fee because we temporarily tied up twice as much as we are entitled to. No, that's not cool at all.