M.D.
I have discovered that my local grocery store is way more expensive than shopping at super Walmart grocery. You get the same quality as the grocery store but a difference in the bill. Maybe shop at a different store and see if there is a financial difference. I agree with the spending of cash. I have gone back to that routine and find that I manage money much better if I have the physical cash in hand versus the debit card. I also agree with using the store brand, there is often little difference in the product but noticeable difference in the price, that does not go for all store brands but for the most part anyway.
Try picking up items you know you will need when you see they are on a good sale. I often browse the clearance section and will pick up clothing for my children. When they need new pants, I already have a few pair ready to go.