You don't have to be a dick at all. I doubt many Uber drivers will admit it publicly but those that can't risk refusing passengers with wheelchairs tend to rate the passenger really low. I've watched it happen to a guy. With his wheelchair he routinely got 1 or 2, without he never had lower than 5. A driver explained that he was concerned about damage to his car boot from carrying wheelchairs. Another said disabled people take too long getting in and out. So, you don't have to be a dick, you just need to be someone they don't want to transport.