Mike,
I agree with you that I would rather have the better performer, but now there is no benefit to keeping something longer. I would calculate that my film rental is at 60%. The film is gone when 1) my contract is over and 2)I can find something else to fill my screen which I expect to gross more than Harry on that particular week.
BTW, I chose Monsters, Inc knowing that I will either skip Harry Potter or bring it in as filler later. I will pick the G rated Disney product every time because I know that it has longer life - everyone in the family can go on the holidays - 10 tickets, please - yum!!!!
Of course, if I had more than 1 screen I would bring it Harry, but dump it at contract end.