I discovered this deal today. Doesn't seem to be advertised on the front page (and no one has picked up on it here yet from what I can tell).
The deal is only for selected brands but some decent buys. I have a cat not a dog but I posted about the Optimum deal in the forums today (only 2 left so posted it as a limited offer) before I went and ordered tonight and noticed it was part of a wider sale.
This is a great deal on Optimum cat dry food though - 6 x 800g bags for $19.11. Woolies sells a bag for $6.50 atm (usual price is $9.80). This deal is half that price.
Discount applied in prices displayed. Offer ends at 11:59 PM (AEDT) on October 29, 2018. The Offer only applies to items sold by Amazon AU on Amazon.com.au. Offers do not apply to purchases made from third-party sellers on Amazon.com.au or orders which are fulfilled by Amazon AU. If you cancel or return any of your Qualifying Items, you will only be refunded the price paid for those Qualifying Items. Offers cannot be used on pre-existing orders. This Offer is subject to availability and may be withdrawn or amended without notice. This Offer is not redeemable for cash. This Offer is non-transferable and may not be resold. Amazon.com.au’s Conditions of Use and Sale apply. Delivery will be applied to each item in accordance with Amazon AU's standard delivery rates and policies. A limit of 3 identical Qualifying Items applies to all orders.
Bargain! Bought a bunch of the cat treats. My cat loves them but they're $9-10 normally at the pet store. Thanks a bunch!