[zzzeek]

visiting every machine is trivial; it occurs daily/weekly for all cash-accepting machines in order to get the cash. This is also not performed by just one low-paid employee; it is typically performed by two people, one of whom is armed and has his weapon drawn. So there's no issue sending out trained personnel to every machine, it happens every day.

Where there is an issue here is that if the software change only applied to credit card sales, there would be an accusation that the machines now favor more affluent customers who can afford to own credit cards.

[snowwrestler]

The people who collect the cash are probably not the people who install, test, and verify software updates.