This whole pokie pre-commitment card thing seems like a complex solution when a far more simple thing would work.
One option would be to go back to having pokies with an arm you pull down. In this way peoples' arms would get sore after a while and they would have to stop feeding their grocery money to the machines. I don't know if it would be 100% effective though. It could just result in a whole lot of problem gambler pensioners with big guns.
The best solution would be to combine pokies with treadmills. The pace would gradually crank up so the pokie addicts would have to continually pick up their pace to avoid falling arse backwards onto the luridly coloured carpet. Only Steve Moneghetti would have the stamina to lose any serious dosh. The best part of the plan is that that the loss in poker machine revenue would be offset by getting formerly sedentary pokie players fitter and creating a lower strain on our health care system.