Some peoples lack of knowledge is actually quite scary; I was shunting once when a driver asked me for his keys back in order to pop his card! I asked him why on Earth he hadn’t told me he was running out of time at least an hour earlier so we could have worked something out and his reply was along the lines of “it doesn’t matter, once my card is out nothing is recorded, so I’ll still be able to get home tonight “ staggering!