Do you honestly think that hundreds of machines capable of authorizing simultaneous credit card transactions and synchronizing mag stripe cards against a central service all receive a price update through direct manual access?
My answer is yes.
(Though for the sake of whomever maintains the system I'd certainly hope to be wrong about this! Either way, an update to all of these machines is likely not the trivial change the author presumes it to be.)
Also you would want to test every machine that gets the update in either case, so you need some kind of tech to touch every machine.
Maybe it's better if the network interactions of these sorts of machines are strictly limited to operational transactions. Maybe it's better if it does takes a human being with a key, guarded by a cop with a gun, to update this software.