@DocBohn @cstross That sounds familiar.
I was once sent to a conference by $multinational and when I got back I dared to walk from the station because I really needed a bit of fresh air after 10 hours on a flight and then the train from the airport.
They demanded I explained why I didn't use a taxi.

(and no, I wasn't going to the office, was going back home, so they didn't even have the excuse to claim that I missed 10 minutes of work because of that).