I also encountered this policy with Alamo at TUS. A manager I questioned acknowledged that there is a 1-hour grace period before the retroactive charges and fee kick in if one does return the car a little late. Nevertheless, this policy, which I have seen with no other agency, coupled with a counter clerk who was tremendously rude in asking what might otherwise be understandable questions ("WHERE are you going to be driving the car? WHAT do you do?"), has caused Alamo to lose my business permanently. As a company, they seem more focused on the leisure traveler, but I didn't assume until this experience that this made them less interested in being courteous and reasonable!