Start A Stockpile
When I say stockpile I’m not saying that you have to purchase 20 bottles of barbeque sauce. Stockpile within reason. If there’s a product that you use daily then buy enough of the product so that you can make it until the next wave.
If you see that some of the items in your stockpile will expire soon, consider dontating them to a foodbank or a family/friend that could use the extra food.
Also, stockpile so that it fits your family. Just because you can get dog treats for free doesn't mean that you HAVE to purchase them if you don't have a dog! If you're going to donate them to your local SPCA then okay but use your manners. If you're not going to really use an item then leave it for someone that can actually use it.