Aus Post satchels - pricing question

Hi, I've just started selling again after a long break. I looked on Aus Post's website for the prepaid satchel prices to set postage prices for my auctions, as I always used to do, but today when I went to buy satchels at the Post Office the small one had a ticket of $9.20 on the shelf, although it said $8.95 on their website. But the receipt shows the price at $8.95 plus another 25 cents fee that I can't for the life of me figure out, whatever it is, it brings it up to that $9.20 total. Can anyone tell me please what the extra cost is for? Do you include it in your postage costs or just absorb it? Thanks! 🙂