At one airline some years ago, the 'little envelopes' were not available at HOTAC check-in, nor were they brought around later...and we had a three day stopover in FRA.
The station manager was nowhere to be found.
So, we all came to the aeroplane on the day of departure, and here is the stn mgr, all neatly pressed and shampoo'd, and he says...'sorry, I forgot to authorise the allowances.
Me (the Commander) says, pay up NOW, in cash, or we don't depart, Bubba.
He paid, and we departed.
HE also departed, the very next week, to parts unknown.