You are correct there is no ban in NSW. Some retail outlets have decided not to provide single use bags and unsurprisingly they just happen to be the same outlets that will benefit from a massive spike in the sale of single use garbage, freezer, sandwich bags etc.
The whole thing is a massive con job, the green bags they are trying to sell are made of woven plastic but take about 5000% more material and energy to produce. They cannot be washed so greatly increase the chance of food poisoning. 60% of the single use bags were reused at least once and will now be replaced with single use bags that customers will purchase. There is also some evidence to suggest the single use bags that did find their way into landfill were of benefit in stabilising and acting as a barrier to reduce gas emissions.
End result is the environment will be worse off, customers will be worse off and out of pocket while big business increases profits.