Lucky you I dont take my shoes off, ever (wear thin-shoes Eccos) and was sent to the carnival last two times.
Asked for the supervisor came over and I told him I was tired of being retaliated against especially since I have been through dozens of airports without having them beep or having to remove them.
He said apologied ( lot of good that does after the fact) and said some of his staff just dont seem to able to fully comply with their instructions.
Sort of surprised me, then he contradicted himself by saying "your shoes fit the profile" ...so I dont expect much change.
Seems instead of selecting the random pax with any sort of partern they just select whoever is ignores their "suggestion to remove"

mike