Mitt and Ann started out like many other young kids. They didn’t have everything handed to them. They lived in lean times.
Mitt’s and her status today, is still based on their youthful experience, and she was touching on that so folks at home could realize she does know what it’s like to try to make ends meet.
Just mentioning these concerns of normal people, does express the thought that she knows what is important to them. I see nothing wrong with that.
Is this a joke? They were rich, they never lived hard, even in college, when they needed to they would cash some of Mitt's stock holdings, or whatever.