On Australia’s Jetstar*- which I sometimes use for a particular route not covered by Qantas - certain fare types (Maxi and/or Flex, think they’re called ....) include an “in-flight voucher” to be applied against the cost of food & drink from the trolley. You can also pay separately for such vouchers, at time of booking, if you’ve selected the very cheapest fare type.


IIRC the voucher entitlement is mentioned within the BP, but I soon discovered that you don’t actually need to present it onboard, simply because the FA’s are very adept at identifying eligible pax from seat numbers ; and then pro-actively offering a choice of F&B items. Works well, and means you don’t have to fiddle around for cash/cards.

(*am talking about their domestic network ... never used them for international, so no idea what happens there)