My post office has now printed signs on the walls saying that they only take cash for postage.
For billpay you can use your Lasercard but not credit card. Imagine paying your credit card bill with another credit card, an endless game.
But I agree it's so backward from AnPost to not take at least laser cards but than again, they would pay a fee for the transaction. Getting a 53 cent stamp an paying it with lasercard would certainly wipe out anything they migth gain.
In other countries these days you can even print postage online (to save the trip to the post office) but here, no sign of that.