You guys crack me up with the conspiracy theories. How come this question was not asked about cars.com, whose prices are also listed highest to lowest by default?
Logically, when ranked from highest to lowest by default, shoppers will scroll through all of the listings while on the way to what they consider their price range and, like most people, will continue to scroll below that hoping for an even better price. Exposure to all dealers' inventory in all price ranges is maximized this way (assuming the shopper hasn't entered a specific price range preference).
If inventory was ranked lowest to highest, shoppers would stop looking when they get to the high end of what they consider their price range and avoid looking at listings beyond that. Higher priced vehicles, even though the prices are justified (CPO, extremely low mileage, still under warranty, etc.) would receive much less exposure. Not many people think, "Gee, let's see if we can find a higher priced one."
By default, consumers see all inventory in a 25 mile radius, so local dealers are prioritized. If the consumer wishes, they can expand their search radius to see dealer inventory from farther away, or restrict it to just 10 miles. They have the option of sorting their searches by year, make/model, price, distance and vehicle mileage.
I don't see the problem.