I was in ABQ once and used Avis. I filled up 10 miles from the airport, and the needle was just slightly on the lower side of the F line (it was an Escape). I know I put as much gas in it as I could plus it was very early in the morning and I wanted to fill up where I knew it was safe. (When I was leaving the airport, I didn't see any gas stations nearby.)

When I checked my receipt online because the counter was closed when I returned the car, they charged me for a full tank of gas. Even though I filled up 10 miles from the airport. I called the counter and the girl said it didn't matter. I called back later in the afternoon and spoke to the manager and he specifically said, after he found out how much they actually put into it, that it was unreasonable to be charged for a full tank when they only had to put in "a little bit." So he adjusted the bill and only charged me 1.50.

By the way, when I mentioned to the first person I spoke to that I filled it up 10 miles away, she said "oh, our policy is that you can fill it up 5 miles from the airport and not be charged."