it'the same at food store. they track what you buy when you swipe DISCOUNT card.
I've heard of people getting fired because they had a friend punch them in at work, and the ez pass for the bridge said he wasn't going over till 10 am, was signed in at 9 am.
another one, this guy got a bad dwi, they found the half case in the back seat was full 2 hrs earlier when he purchased the case from the store with his discount card. they make you think it's for your better, it's not, it's for them to keep track of what you're doing.