Originally Posted by TWAforever
Sure enough, I have a $50 charge pending on my credit card.
Have you presented that card upon check-in? If so, the "charge" you are referring to, is likely not really a charge, but simply a [pre-]authorization for any incidental charges you might have incurred. If your reservation was prepaid, and you had no incidental charges, the said [pre-]authorization will never become a charge, as it will eventually disappear (after a period of 1-45 days).