But what if this taxi driver really did toss around the interviewee's expensive luggage, with his best interview clothes and perhaps some materials or documents for an important interview the next day? Does the taxi driver report back, yea he got upset, but it was my fault? What if the interviewee just got off a long flight, wants to rest up for the interview, and isn't really up for chatting with a taxi driver? Does the taxi driver report back that he was rude, wouldn't talk?

I will agree that if the person is a total rageaholic nutcase, passing that info along to the company is valuable information. But reporting on anything else -- asking the driver to keep quiet, requesting he take better care of luggage, asking for a specific route, turning down the radio, whatever -- I'd be more suspicious that the driver is a nuisance than the interviewee has character flaws.

This subthread is really getting absurd. It's a perfectly good test to hear whether a candidate mistreated someone who they might perceive to be beneath them, and only severely asocial nerds would interpret Op's anecdote as if they put this taxi driver into the CI/CD pipeline to pass/fail candidates.

It's an urban legend, a tired old trope of "gotcha!" style human observation that today is commonly used on the bottom-of-the-barrel TV talk shows like Maury Povich. The "absurd" part is that despite the tons of comments here, you haven't realized that yet. Lol.