In our area, the "yes" and "no" buttons are not consistently placed from store to store. I'm not talking just Walgreen's, but at the grocery store I use most, and Staples(who knew you could get cash back??), and Target.

Sometimes I hit the "no" button when I mean "yes". So I just let it go. I don't want to hold up the line.

At Staples, I hit "yes" probably because I was so shocked at the question. So I just took $20. Again, not to hold up the line.

But, really, OP is at fault here. SHE knew she'd requested cash back. She should have waited there and compared her receipt with the transaction.