It's also bizarre to me that the company would have a "trusted taxi driver". A trusted driver for executives or something might make sense, but a trusted driver who isn't employed by your organization that you specifically route candidates through? It just doesn't sound like the type of thing that happens much to me.
Finally, on the subject of people being randomly rude to taxi drivers, never having been a taxi driver I don't have real first hand information. I did ride a public city bus multiple times a day for years though and the number of people who I witnessed being rude to the driver, who were not visibly drunk or homeless, is zero. It just doesn't fit with my experience of humanity to think that, in a typical daytime taxi ride you're going to get much absurdly inappropriate behavior - i.e behavior that would rise to the level of disqualifying the candidate. Maybe if the taxi driver were a woman I'd believe it, but I bet the vast majority of people would just say where they wanted to go and little else.
