Part of the reason she "got away with it" was because she gave the appearance of a "grandmother" type, so I guess grandmothers don't steal. And I guess the clerks just figured she really _did_ forget her checkbook. That would never work for me, even though I have handed a grocery store discount card to a clerk to charge my purchases to (the clerk was _not_ amused). I'm definitely forgetful, but I guess I look too shady to be able to pull a stunt like that off.
The lawyer could toss in some stuff about hormones (the PMS defense worked for some women) and how this distorted his/her client's mind between what is right and wrong. I hope the woman does not get any jail time, because though she commited a felony (I think it's a felony), if the yarn was given back to the store unused, there was little damage done. Maybe the yarn shop should hire her to watch out for the other customers. Obviously, if she pulled off this caper, other folks could, too. And perhaps they would give her a discount on the yarn.
I don't know if my defense would work. But I do know if I were her lawyer, I wouldn't wait while she went out to her car to get her checkbook to pay me.