Camry might also be a little easier to maneuver around Short North, traffic, BS airport traffic. Gas savings alone are probably huge. Making a dozen runs to the airport would really eat into profit I would imagine.
Plus its just less creepy. I hate getting some POS Crown Vic as an Uber, but its luck of the draw. I do often get a lot of older Mercedes ect...like a C300 ect. I know they are technically in the beater category, but you feel a little more baller getting dropped off in a Merc. Junk or not.