Is there any other cost-effective way to get to the airport? Were you planning on another one-way to come back?
It's not just Avis or one location. Last summer I almost ran into a similar problem with Avis in a Dallas suburb. I made the reservation one-way to DFW for a week, with trips planned to the Mid Cities and Waco in between. I called the location in advance, and they said the reservation shouldn't have gone through. They don't have enough cars to lose for one-ways, even within the same region. If I were to show up, they would only give me a car if I could return it there. I couldn't. I'd be at least an hour away on the other side of the area and rushing to catch a flight. They said to rent from an airport. Luckily the one-way rates were similar from DAL, so I did. Other than being assigned a free upgrade from midsize to a used mini gas guzzling SUV, that needed to be refueled practically every day while gas prices were rising, everything worked out ok.
Lately, I see angry comments on the Enterprise Facebook page. Neighborhood stores canceled one-ways that people were relying on instead of a taxi to go to major airports. It's becoming a common theme. But that makes it impossible to plan. If you only kind of sorta needed a car, you would kinda sorta not bother making this kind of reservation.