And how do they define 'lack of use'? What's the cutoff?
For this particular card, "Lack of use" meant that I had used it a few times during the course the year, and had paid the balance in full each time I used it. It was the card I kept for emergency use; I managed to wiggle out of most of my financial emergencies last year without resorting to the emergency card.
They wanted me to carry a balance, or else I wasn't welcome to be their customer anymore. They said in 6 months I could reapply for a card with a higher interest rate. I said, Fuck 'em.