Why did you come in, then?

Today a patron came in to 'sign up for a library card,' but when we checked her name in our system it turned out that she used to have a card a long time ago and owed us about $50 for lost books, so we couldn't issue her a new card until she paid her fine down most of the way. I was helping someone else so I didn't hear most of her discussion with my coworker. All I knew was that a couple minutes later, she stomped past my desk muttering angrily "I didn't want to read anyway!"