I know on Dash Flights, grog is free after 4pm during the week, but the F/A's aren't allowed to make an announcement to that effect. If somebody asks, they get it, which of course starts the whole cabin asking.
About a year ago on the SYD-CB shuttle run (now city flyer), a survey was conducted with passengers as to whether they would prefer alcohol or tea/coffee served. Apparently alcohol won, and for a while, the tech crews had to carry a flask of coffee if they wanted one, as QF no longer stocked that flight with it.