My wife booked room at the Fairfield Inn Phily Airport for a stay in November. I saw a pending credit card charge for the full room rate plus tax. I reviewed the reservation and it stated "Saturday, November XX, 2015 - Sunday, November XX, 2015 (1 night , Regular rate, prepay in full ).
When the room is being booked it says "regular rate" with nothing stated about the prepay in full. If you click on "about this rate" it did mention prepay. However, I never felt the need to click "about this rate" when I was booking a regular rate room.
I called Marriott customer care and was advised that all rooms(for my night) at this Hotel were regular rate, pre-pay in full. I was told it is always good to check "about this rate". I said I should not need to if booking a regular rate. I can cancel 24 hours before arrival and get my money back.
So Marriot is getting the float on the credit card payment.